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All questions of Matter in Our Surroundings for Grade 9 Exam
Can you explain the answer of this question below:Transpiration from the leaves of trees is an example of:- A:Evaporation
- B:Sublimation
- C:Condensation
- D:Diffusion
The answer is a.
Transpiration from the leaves of trees is an example of:
A:
Evaporation
B:
Sublimation
C:
Condensation
D:
Diffusion
|
Amit Sharma answered |
Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
The change of state from solid to liquid known as –
- a)Melting
- b)Boiling
- c)Sublimation
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
The change of state from solid to liquid known as –
a)
Melting
b)
Boiling
c)
Sublimation
d)
None of these
|
|
Amit Sharma answered |
The change of state from solid to liquid is known as Melting. This is a process in which a solid substance changes into a liquid on heating. Heat energy is required to break the bonds between molecules, allowing them to move around freely. This process is also known as fusion, and the amount of energy required is called the latent heat of fusion. In a phase diagram such as Figure 12.4.1, the melting point is the temperature at which a substance can transition from a solid to a liquid.
Natural phenomenon like fog, mist or frost are caused due to:- a)Evaporation
- b)Transpiration
- c)Freezing
- d)Condensation
Correct answer is option 'D'. Can you explain this answer?
Natural phenomenon like fog, mist or frost are caused due to:
a)
Evaporation
b)
Transpiration
c)
Freezing
d)
Condensation
|
Jyoti Kapoor answered |
Fog, mist or frost are due to condensation, depending upon the physical conditions of atmosphere.
Which substance undergo sublimation process –
- a)Naphthalene
- b)Br2
- c)Ice
- d)N2
Correct answer is option 'A'. Can you explain this answer?
Which substance undergo sublimation process –
a)
Naphthalene
b)
Br
2c)
Ice
d)
N2
|
Ruhi Shah answered |
Some substances that undergo sublimation include dry ice (solid carbon dioxide), iodine, camphor, and napthalene.
Under which of the following conditions we can boil water at room temperature?
- a)At low pressure
- b)At moderate pressure
- c)At very high pressure
- d)At atmospheric pressure
Correct answer is option 'A'. Can you explain this answer?
Under which of the following conditions we can boil water at room temperature?
a)
At low pressure
b)
At moderate pressure
c)
At very high pressure
d)
At atmospheric pressure
|
Varun Kumar answered |
At low pressure
Explanation: Boiling occurs when the vapor pressure of a liquid equals the external pressure. At lower pressures, the boiling point of water decreases. So, if the external pressure is reduced significantly (below atmospheric pressure), water can boil at room temperature. This phenomenon can be observed in a vacuum chamber, where the pressure is significantly reduced, allowing water to boil at room temperature.
Explanation: Boiling occurs when the vapor pressure of a liquid equals the external pressure. At lower pressures, the boiling point of water decreases. So, if the external pressure is reduced significantly (below atmospheric pressure), water can boil at room temperature. This phenomenon can be observed in a vacuum chamber, where the pressure is significantly reduced, allowing water to boil at room temperature.
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility.- a)True
- b)False
Correct answer is 'A'. Can you explain this answer?
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility.
a)
True
b)
False
|
Hansa Sharma answered |
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility. This is possible because of the large inter particle distance and weak force of attraction between the particles of gas.
The boiling point of water on kelvin scale is –- a)573 K
- b)273 K
- c)373 K
- d)100 K
Correct answer is 'C'. Can you explain this answer?
The boiling point of water on kelvin scale is –
a)
573 K
b)
273 K
c)
373 K
d)
100 K
|
Om Menon answered |
Formula to change the value of celcious into kelvin is K=C+273 As we know that boiling point of water is 100 c. SO, K=100+273 K =373 k.
Gases have highest rate of diffusion among all the three states of matter.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Gases have highest rate of diffusion among all the three states of matter.
a)
True
b)
False
|
|
Amit Kumar answered |
Diffusion is the property of matter which is based on the motion of its particles. Diffusion occurs in gases, liquids and solids. Diffusion is fastest in gases and slowest in solids. The rate of diffusion increases on increasing the temperature of the diffusing substance.
Can you explain the answer of this question below:Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Matter in our surroundings" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 Science Q. Which of the following has the strongest interparticle force at the room temperature?- A:Nitrogen
- B:Mercury
- C:Iron
- D:Chalk
The answer is C.
Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Matter in our surroundings" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 Science
Q. Which of the following has the strongest interparticle force at the room temperature?
A:
Nitrogen
B:
Mercury
C:
Iron
D:
Chalk
|
Sharanya shah answered |
Higher the melting point of a substance, greater will be the force of attraction between particles. The melting point of iron is considerably high, so the force of attraction between its particles is higher.
Convert the temperature of 373°C to the kelvin scale ?- a)646 K
- b)546 K
- c)300 K
- d)500 K
Correct answer is option 'A'. Can you explain this answer?
Convert the temperature of 373°C to the kelvin scale ?
a)
646 K
b)
546 K
c)
300 K
d)
500 K
|
Nikhil Mehra answered |
We know that ,K = °C + 273.15
= 373 deg C + 273.15 deg C
= 646.15 deg C
Water has boiling point equal to 100°C.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Water has boiling point equal to 100°C.
a)
True
b)
False
|
Zzz answered |
It is true as boiling point of water is 100 degree Celsius, the statement is absolutely true and correct
Camphor changes to gaseous state without changing into liquid.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Camphor changes to gaseous state without changing into liquid.
a)
True
b)
False
|
|
Jithin Das answered |
It's true because camphor is sublime and it changes directly into gas without passing through the state of liquid. The process in which solid directly changes into gas without passing through the state of liquid is called sublimation.
The process of change of a liquid into vapour at any temperature is called –- a)Diffusion
- b)Evaporation
- c)Cooling
- d)Heating
Correct answer is option 'B'. Can you explain this answer?
The process of change of a liquid into vapour at any temperature is called –
a)
Diffusion
b)
Evaporation
c)
Cooling
d)
Heating
|
Ravi Verma answered |
The process of conversion of a substance from the liquid state to its vapor state at any temperature below boiling point is called evaporation or vaporization.
Can you explain the answer of this question below:Evaporation causes heating
- A:
True
- B:
False
The answer is B.
Evaporation causes heating
True
False
|
|
Arjun Sharma answered |
When evaporation occurs then than the liquid (mostly water) absorbs all the heat from the surroundings and take it with it and we feel cool. evaporation causes cooling effect because the heat energy is abosorbed by surrounding particles.
Name the process by which a drop of ink spreads in a beaker of water –
- a)Diffusion
- b)Vaporization
- c)Condensation
- d)Sublimation
Correct answer is option 'A'. Can you explain this answer?
Name the process by which a drop of ink spreads in a beaker of water –
a)
Diffusion
b)
Vaporization
c)
Condensation
d)
Sublimation
|
Prachi Rathore answered |
A drop of ink spreads in a beaker of water through diffusion. This is because the particles in liquids can move around each other, which means that eventually they are evenly mixed. Diffusion is the process of a substance spreading out to evenly fill its container or environment. In a solution, a concentrated solute diffuses to spread evenly in its solvent. concentration to low concentration.
The temperature at which liquid starts boiling at atmospheric pressure known as –- a)Melting point
- b)Boiling point
- c)Latent heat
- d)Condensation
Correct answer is option 'B'. Can you explain this answer?
The temperature at which liquid starts boiling at atmospheric pressure known as –
a)
Melting point
b)
Boiling point
c)
Latent heat
d)
Condensation
|
Sarita Reddy answered |
Boiling occurs when the vapor pressure reaches or exceeds the surrounding pressure from the atmosphere or whatever else is in contact with the liquid. At standard atmospheric pressure (1 atmosphere = 0.101325 MPa), water boils at approximately 100 degrees Celsius.
Fluids are –- a)Liquids and gases
- b)Solids and gases
- c)Liquids and solids
- d)Only solids
Correct answer is option 'A'. Can you explain this answer?
Fluids are –
a)
Liquids and gases
b)
Solids and gases
c)
Liquids and solids
d)
Only solids
|
|
Arvind Singh answered |
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas, and to some extent, plastic solids.
The process for the change of a solid directly into its vapour is called –- a)Evaporation
- b)Ebullition
- c)Condensation
- d)Sublimation
Correct answer is option 'D'. Can you explain this answer?
The process for the change of a solid directly into its vapour is called –
a)
Evaporation
b)
Ebullition
c)
Condensation
d)
Sublimation
|
Sanchita Choudhury answered |
Sublimation is the process through which the solid substance changes directly into vapours or gaseous state without passing through liquid state. Dry ice is a common example of this process.
Convert the temperature of 270 K to the celsius scale –- a)– 3°C
- b)– 4°C
- c)2°C
- d)5°C
Correct answer is option 'A'. Can you explain this answer?
Convert the temperature of 270 K to the celsius scale –
a)
– 3°C
b)
– 4°C
c)
2°C
d)
5°C
|
|
Amit Kumar answered |
We know that °C = K - 273.15
C= K - 273
C= 270 - 273
C = -3
C= 270 - 273
C = -3
Plasma is the.......... state of matter –- a)First
- b)Second
- c)Third
- d)Fourth
Correct answer is option 'D'. Can you explain this answer?
Plasma is the.......... state of matter –
a)
First
b)
Second
c)
Third
d)
Fourth
|
|
Ananya Sharma answered |
A plasma is a hot ionized gas consisting of approximately equal numbers of positively charged ions and negatively charged electrons. The characteristics of plasmas are significantly different from those of ordinary neutral gases so that plasmas are considered a distinct "fourth state of matter."
Which statement regarding the effect of humidity on evaporation is correct?- a)With the increase in humidity, rate of evaporation decreases.
- b)Humidity sometimes increases and sometimes decreases the rate of evaporation.
- c)Humidity has no effect on evaporation.
- d)With the decrease in humidity, rate of evaporation decreases.
Correct answer is option 'A'. Can you explain this answer?
Which statement regarding the effect of humidity on evaporation is correct?
a)
With the increase in humidity, rate of evaporation decreases.
b)
Humidity sometimes increases and sometimes decreases the rate of evaporation.
c)
Humidity has no effect on evaporation.
d)
With the decrease in humidity, rate of evaporation decreases.
|
|
Wahid Khan answered |
Humidity refers to presence of vapour in air. So, if humidity increases then the rate of evaporation decreases as vapours in air are already present.
The melting point of ice is –- a)0°C
- b)4°C
- c)5°C
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
The melting point of ice is –
a)
0°C
b)
4°C
c)
5°C
d)
None of these
|
Geetika Shah answered |
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. For ice, the melting point is 0°C at which ice a solid turn to water.
Dry ice is –- a)Water in solid state
- b)Water in gaseous state
- c)CO2 in liquid state
- d)CO2 in solid state
Correct answer is option 'D'. Can you explain this answer?
Dry ice is –
a)
Water in solid state
b)
Water in gaseous state
c)
CO2 in liquid state
d)
CO2 in solid state
|
|
Ananya Sharma answered |
Dry ice, sometimes referred to as "cardice", is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue.
The physical state of matter which can be easily compressed –- a)Liquid
- b)Gas
- c)Solid
- d)None of these
Correct answer is 'B'. Can you explain this answer?
The physical state of matter which can be easily compressed –
a)
Liquid
b)
Gas
c)
Solid
d)
None of these
|
|
Jyoti Kapoor answered |
The physical state of matter which can be easily compressed is the gaseous state as thy have more interparticular space and the particles present in them have very little force of attraction. So they can be easily compressed in contrast to solid and liquid.
Condensing is opposite to evaporating and freezing is opposite to melting.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Condensing is opposite to evaporating and freezing is opposite to melting.
a)
True
b)
False
|
Tanishq Patel answered |
Explanation:
Condensing and Evaporating:
- Condensing is the process by which a substance changes from a gas to a liquid state, usually by cooling. This occurs when the particles of the gas slow down and come together to form a liquid.
- Evaporating, on the other hand, is the process by which a substance changes from a liquid to a gas state, usually by heating. This occurs when the particles of the liquid gain enough energy to break free and become a gas.
Opposites:
- Condensing and evaporating are indeed opposite processes. When a substance condenses, it goes from a gas to a liquid state, whereas when it evaporates, it goes from a liquid to a gas state. These processes are reverse of each other and involve opposite changes in the state of matter.
Freezing and Melting:
- Freezing is the process by which a substance changes from a liquid to a solid state, usually by cooling. This occurs when the particles of the liquid slow down and come together to form a solid.
- Melting, on the other hand, is the process by which a substance changes from a solid to a liquid state, usually by heating. This occurs when the particles of the solid gain enough energy to break free and become a liquid.
Opposites:
- Freezing and melting are indeed opposite processes. When a substance freezes, it goes from a liquid to a solid state, whereas when it melts, it goes from a solid to a liquid state. These processes are reverse of each other and involve opposite changes in the state of matter.
Condensing and Evaporating:
- Condensing is the process by which a substance changes from a gas to a liquid state, usually by cooling. This occurs when the particles of the gas slow down and come together to form a liquid.
- Evaporating, on the other hand, is the process by which a substance changes from a liquid to a gas state, usually by heating. This occurs when the particles of the liquid gain enough energy to break free and become a gas.
Opposites:
- Condensing and evaporating are indeed opposite processes. When a substance condenses, it goes from a gas to a liquid state, whereas when it evaporates, it goes from a liquid to a gas state. These processes are reverse of each other and involve opposite changes in the state of matter.
Freezing and Melting:
- Freezing is the process by which a substance changes from a liquid to a solid state, usually by cooling. This occurs when the particles of the liquid slow down and come together to form a solid.
- Melting, on the other hand, is the process by which a substance changes from a solid to a liquid state, usually by heating. This occurs when the particles of the solid gain enough energy to break free and become a liquid.
Opposites:
- Freezing and melting are indeed opposite processes. When a substance freezes, it goes from a liquid to a solid state, whereas when it melts, it goes from a solid to a liquid state. These processes are reverse of each other and involve opposite changes in the state of matter.
CO2 can be easily liquified and even solidified because
- a)It has weak forces of attraction
- b)It has a low melting point and low boiling point.
- c)It has more intermolecular space
- d)It is present in atmosphere
Correct answer is option 'B'. Can you explain this answer?
CO2 can be easily liquified and even solidified because
a)
It has weak forces of attraction
b)
It has a low melting point and low boiling point.
c)
It has more intermolecular space
d)
It is present in atmosphere
|
|
Ravi Verma answered |
Carbon dioxide is a gas and has a weak intermolecular force of attraction between its molecules. It can be easily solidified and even liquified because it has a low melting point and low boiling point.
Can you explain the answer of this question below:Particles of matter are continuously moving. What is the effect of rise in temperature on moving particles?
- A:
With rise in temperature, particles move faster
- B:
With rise in temperature, particles stop moving
- C:
With rise in temperature, particles move slowly
- D:
None of the above
The answer is a.
Particles of matter are continuously moving. What is the effect of rise in temperature on moving particles?
With rise in temperature, particles move faster
With rise in temperature, particles stop moving
With rise in temperature, particles move slowly
None of the above
|
|
Suyash Nambiar answered |
Effect of rise in temperature on moving particles
When the temperature of a substance is raised, the kinetic energy of the particles in the substance increases. This increased kinetic energy results in faster movement of the particles. Therefore, option A is correct. The movement of particles increases with an increase in temperature.
The movement of particles is directly proportional to the temperature of the substance. As the temperature of the substance increases, the particles gain more kinetic energy. This energy is utilized by the particles to move faster. Consequently, the increased speed of the particles leads to an increase in the overall energy of the substance.
In conclusion, the effect of rise in temperature on moving particles is that they move faster. This is due to the increased kinetic energy gained by the particles as the temperature of the substance is raised.
- A: With rise in temperature, particles move faster
- B: With rise in temperature, particles stop moving
- C: With rise in temperature, particles move slowly
- D: None of the above
When the temperature of a substance is raised, the kinetic energy of the particles in the substance increases. This increased kinetic energy results in faster movement of the particles. Therefore, option A is correct. The movement of particles increases with an increase in temperature.
The movement of particles is directly proportional to the temperature of the substance. As the temperature of the substance increases, the particles gain more kinetic energy. This energy is utilized by the particles to move faster. Consequently, the increased speed of the particles leads to an increase in the overall energy of the substance.
In conclusion, the effect of rise in temperature on moving particles is that they move faster. This is due to the increased kinetic energy gained by the particles as the temperature of the substance is raised.
Why do naphthalene balls disappear with time without leaving any solid behind?- a)Due to melting
- b)Due to freezing
- c)Due to boiling
- d)Due to sublimation
Correct answer is option 'D'. Can you explain this answer?
Why do naphthalene balls disappear with time without leaving any solid behind?
a)
Due to melting
b)
Due to freezing
c)
Due to boiling
d)
Due to sublimation
|
Aashi answered |
The correct answer is due to sublimation because naphthalene balls are sublime substance therefore the process of sublimation takes place in this process!!
The temperature at which a liquid changes into its gaseous form is called _________.- a)boiling point
- b)melting point
- c)freezing point
- d)triple point
Correct answer is option 'A'. Can you explain this answer?
The temperature at which a liquid changes into its gaseous form is called _________.
a)
boiling point
b)
melting point
c)
freezing point
d)
triple point
|
|
Mainak Yadav answered |
Boiling Point:
The temperature at which a liquid changes into its gaseous form is called the boiling point.
Explanation:
When a liquid is heated, the kinetic energy of its molecules increases. At a certain temperature, the kinetic energy of the molecules becomes sufficient to overcome the intermolecular forces holding the liquid together. At this point, the liquid starts to turn into its gaseous form, which is called vaporization. The temperature at which this happens is called the boiling point.
Factors Affecting Boiling Point:
The boiling point of a liquid depends on various factors such as:
1. Pressure: The boiling point of a liquid decreases with a decrease in pressure and increases with an increase in pressure.
2. Intermolecular Forces: The boiling point of a liquid increases with an increase in intermolecular forces.
3. Molecular Size: The boiling point of a liquid increases with an increase in molecular size.
Importance of Boiling Point:
The boiling point of a liquid is an important physical property used to identify and classify liquids. It also plays a crucial role in various industrial processes such as distillation, fractional distillation, and steam generation.
Conclusion:
In conclusion, the boiling point is the temperature at which a liquid changes into its gaseous form. It depends on various factors such as pressure, intermolecular forces, and molecular size. The boiling point is an important physical property and plays a crucial role in various industrial processes.
The temperature at which a liquid changes into its gaseous form is called the boiling point.
Explanation:
When a liquid is heated, the kinetic energy of its molecules increases. At a certain temperature, the kinetic energy of the molecules becomes sufficient to overcome the intermolecular forces holding the liquid together. At this point, the liquid starts to turn into its gaseous form, which is called vaporization. The temperature at which this happens is called the boiling point.
Factors Affecting Boiling Point:
The boiling point of a liquid depends on various factors such as:
1. Pressure: The boiling point of a liquid decreases with a decrease in pressure and increases with an increase in pressure.
2. Intermolecular Forces: The boiling point of a liquid increases with an increase in intermolecular forces.
3. Molecular Size: The boiling point of a liquid increases with an increase in molecular size.
Importance of Boiling Point:
The boiling point of a liquid is an important physical property used to identify and classify liquids. It also plays a crucial role in various industrial processes such as distillation, fractional distillation, and steam generation.
Conclusion:
In conclusion, the boiling point is the temperature at which a liquid changes into its gaseous form. It depends on various factors such as pressure, intermolecular forces, and molecular size. The boiling point is an important physical property and plays a crucial role in various industrial processes.
Latent heat of fusion is the amount of heat energy required to change:- a)1 kg of solid into its gaseous state at its boiling point
- b)1 kg of liquid into its solid state at its freezing point
- c)1 kg of liquid into its gaseous state at its boiling point
- d)1 kg of solid into its liquid state at its melting point
Correct answer is option 'D'. Can you explain this answer?
Latent heat of fusion is the amount of heat energy required to change:
a)
1 kg of solid into its gaseous state at its boiling point
b)
1 kg of liquid into its solid state at its freezing point
c)
1 kg of liquid into its gaseous state at its boiling point
d)
1 kg of solid into its liquid state at its melting point
|
|
Ravi Verma answered |
The enthalpy of fusion is a latent heat, because during melting the heat energy needed to change the substance from solid to liquid at atmospheric pressure is latent heat of fusion, as the temperature remains constant during the process.
Condensation process is –- a)Change of state from gas to liquid
- b)Change of state from liquid to gas
- c)Change of state from gas to solid
- d)Change of state from solid to liquid
Correct answer is option 'A'. Can you explain this answer?
Condensation process is –
a)
Change of state from gas to liquid
b)
Change of state from liquid to gas
c)
Change of state from gas to solid
d)
Change of state from solid to liquid
|
|
Sharad Chavan answered |
The process of changing from gaseous state to liquid state on cooling is called condensation.
Mixture containing ions ,atoms and electrons is known as- a)solid
- b)liquid
- c)plasma
- d)gas
Correct answer is option 'C'. Can you explain this answer?
Mixture containing ions ,atoms and electrons is known as
a)
solid
b)
liquid
c)
plasma
d)
gas
|
Nabanita Mishra answered |
Mixture containing ions ,atoms and electrons is known as plasma
What is volume of gases?- a)Definite
- b)Almost Nil
- c)Large
- d)Take the volume of container
Correct answer is option 'D'. Can you explain this answer?
What is volume of gases?
a)
Definite
b)
Almost Nil
c)
Large
d)
Take the volume of container
|
|
Jyoti Kapoor answered |
A gas is a substance with no definite volume and no definite shape. Solids and liquids have volumes that do not change easily. A gas, on the other hand, has a vol- ume that changes to match the volume of its container. The molecules in a gas are very far apart compared with the molecules in a solid or a liquid.
How does the state of matter change during fusion process?- a)Gas changes to solid
- b)Solid changes to liquid
- c)Gas changes to liquid
- d)Liquid changes to gas
Correct answer is option 'B'. Can you explain this answer?
How does the state of matter change during fusion process?
a)
Gas changes to solid
b)
Solid changes to liquid
c)
Gas changes to liquid
d)
Liquid changes to gas
|
Anshika answered |
If we will take the example of ice ,a solid so when melting or fusion takes place ice convert to water a liquid
Transpiration from the leaves of trees is an example of:- a)Evaporation
- b)Sublimation
- c)Condensation
- d)Diffusion
Correct answer is option 'A'. Can you explain this answer?
Transpiration from the leaves of trees is an example of:
a)
Evaporation
b)
Sublimation
c)
Condensation
d)
Diffusion
|
|
Hansa Sharma answered |
Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
Which of the following is not correct?
- a)SI unit of temperature is kelvin
- b)SI unit of pressure is Newton
- c)SI unit of density is kg/m3
- d)1 litre = 1000 cm3 - 1 dm3
Correct answer is option 'B'. Can you explain this answer?
Which of the following is not correct?
a)
SI unit of temperature is kelvin
b)
SI unit of pressure is Newton
c)
SI unit of density is kg/m3
d)
1 litre = 1000 cm3 - 1 dm3
|
|
Kritika Bose answered |
SI Units of Measurement
SI units are the International System of Units, which is the modern form of the metric system. It is used in scientific and technical fields as a standard system of measurement. The SI system has seven base units, which are used to derive all other units of measurement.
SI Units of Temperature, Pressure, Density and Volume
Temperature: The SI unit of temperature is Kelvin (K), not Celsius (°C).
Pressure: The SI unit of pressure is Pascal (Pa), not atm (atmosphere).
Density: The SI unit of density is kilograms per cubic meter (kg/m3).
Volume: The SI unit of volume is cubic meter (m3). However, liter (L) is also commonly used as a non-SI unit of volume. 1 L = 1000 cm3 = 1 dm3.
Conclusion
Option B is not correct because the SI unit of pressure is Pascal (Pa), not atm (atmosphere). Atm is a non-SI unit of pressure. Therefore, the correct answer is option B.
SI units are the International System of Units, which is the modern form of the metric system. It is used in scientific and technical fields as a standard system of measurement. The SI system has seven base units, which are used to derive all other units of measurement.
SI Units of Temperature, Pressure, Density and Volume
Temperature: The SI unit of temperature is Kelvin (K), not Celsius (°C).
Pressure: The SI unit of pressure is Pascal (Pa), not atm (atmosphere).
Density: The SI unit of density is kilograms per cubic meter (kg/m3).
Volume: The SI unit of volume is cubic meter (m3). However, liter (L) is also commonly used as a non-SI unit of volume. 1 L = 1000 cm3 = 1 dm3.
Conclusion
Option B is not correct because the SI unit of pressure is Pascal (Pa), not atm (atmosphere). Atm is a non-SI unit of pressure. Therefore, the correct answer is option B.
Intermolecular forces are maximum in solids and minimum in gases.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Intermolecular forces are maximum in solids and minimum in gases.
a)
True
b)
False
|
Arjun Desai answered |
Intermolecular force refers to the force that exists between two or more molecules.
Intermolecular force of attraction is maximum in solids.
This is because molecules in solid remain very close to each other which allot a definite shape to the objects that are solid.
It is lesser in liquids and least in the gases.
Kinetic energy of molecules is directly proportional to- a)Temperature
- b)Pressure
- c)Both (a) and (b)
- d)Atmospheric pressure
Correct answer is option 'A'. Can you explain this answer?
Kinetic energy of molecules is directly proportional to
a)
Temperature
b)
Pressure
c)
Both (a) and (b)
d)
Atmospheric pressure
|
|
Akshat Bhatt answered |
Because when we increase temperature the molecules gain kinetic energy and are free to flow but when talking about pressure and atmospheric pressure, as they increase the kinetic energy of molecules decreases.
In which state does water exist at 50° C?- a)Liquid
- b)Solid
- c)Gas
- d)None of the above
Correct answer is option 'A'. Can you explain this answer?
In which state does water exist at 50° C?
a)
Liquid
b)
Solid
c)
Gas
d)
None of the above
|
|
Abhishek Rane answered |
°F?
Water exists as a liquid in all 50 states of the United States at 50°F, as well as in most parts of the world.
Water exists as a liquid in all 50 states of the United States at 50°F, as well as in most parts of the world.
Kinetic energy of molecules is directly proportional to - a)Temperature
- b)Pressure
- c)Both (a) and (b)
- d)Atmospheric pressure
Correct answer is option 'A'. Can you explain this answer?
Kinetic energy of molecules is directly proportional to
a)
Temperature
b)
Pressure
c)
Both (a) and (b)
d)
Atmospheric pressure
|
Ishan Yadav answered |
The kinetic energy of molecules
K=3/2 kB. T
K = average kinetic energy per molecule of gas (J)
kB = Boltzmann's constant ()
T = temperature (k)
K=3/2 kB. T
K = average kinetic energy per molecule of gas (J)
kB = Boltzmann's constant ()
T = temperature (k)
Which of the following statements is incorrect?
- a)Matter is made up of particles
- b)Particles of matter are always in state of motion
- c)Matter is continuous in nature
- d)Particles of matter attract each other
Correct answer is option 'C'. Can you explain this answer?
Which of the following statements is incorrect?
a)
Matter is made up of particles
b)
Particles of matter are always in state of motion
c)
Matter is continuous in nature
d)
Particles of matter attract each other
|
|
Bhaskar Chatterjee answered |
Incorrect Statement: Matter is continuous in nature.
Explanation:
Matter is made up of small particles called atoms and molecules that have mass and occupy space. These particles are not continuous but are separated by empty spaces. Therefore, the statement that "matter is continuous in nature" is incorrect.
Evidence Supporting the Correct Statements:
a) Matter is made up of particles:
The concept of matter being made up of small particles was first proposed by the Greek philosopher Democritus in the 5th century BC. This idea was later supported by scientists like John Dalton, who proposed the atomic theory of matter in the 19th century. Today, we know that matter is made up of atoms and molecules.
b) Particles of matter are always in a state of motion:
Particles of matter are always in motion, even when they appear to be at rest. This motion can be either random or organized. The kinetic theory of matter explains that the temperature of matter is related to the speed of its particles. When matter is heated, the particles move faster and vice versa.
d) Particles of matter attract each other:
Particles of matter attract each other due to the presence of forces like gravitational, electric, and magnetic forces. These forces allow particles to stick together and form larger structures like molecules, crystals, and even planets.
Conclusion:
In conclusion, the statement that "matter is continuous in nature" is incorrect. Matter is made up of small particles that are separated by empty spaces. These particles are always in motion and attract each other due to the presence of forces.
Explanation:
Matter is made up of small particles called atoms and molecules that have mass and occupy space. These particles are not continuous but are separated by empty spaces. Therefore, the statement that "matter is continuous in nature" is incorrect.
Evidence Supporting the Correct Statements:
a) Matter is made up of particles:
The concept of matter being made up of small particles was first proposed by the Greek philosopher Democritus in the 5th century BC. This idea was later supported by scientists like John Dalton, who proposed the atomic theory of matter in the 19th century. Today, we know that matter is made up of atoms and molecules.
b) Particles of matter are always in a state of motion:
Particles of matter are always in motion, even when they appear to be at rest. This motion can be either random or organized. The kinetic theory of matter explains that the temperature of matter is related to the speed of its particles. When matter is heated, the particles move faster and vice versa.
d) Particles of matter attract each other:
Particles of matter attract each other due to the presence of forces like gravitational, electric, and magnetic forces. These forces allow particles to stick together and form larger structures like molecules, crystals, and even planets.
Conclusion:
In conclusion, the statement that "matter is continuous in nature" is incorrect. Matter is made up of small particles that are separated by empty spaces. These particles are always in motion and attract each other due to the presence of forces.
The hardness of solids is due to the fact that their particles:- a)Have strong forces of attraction between them.
- b)Are held very close to each other.
- c)Have fixed positions.
- d)All of the above.
Correct answer is option 'D'. Can you explain this answer?
The hardness of solids is due to the fact that their particles:
a)
Have strong forces of attraction between them.
b)
Are held very close to each other.
c)
Have fixed positions.
d)
All of the above.
|
Vikram Khanna answered |
Liquids will flow and fill up any shape of container. Solids like to hold their shape. In the same way that a large solid holds its shape, the atoms inside of a solid are not allowed to move around too much. Atoms and molecules in liquids and gases are bouncing and floating around, free to move where they want.
Assertion (A): Water droplets form on the outer surface of a glass containing ice-cold water.
Reason (R): Water evaporates from the glass and condenses on the outside.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'C'. Can you explain this answer?
Assertion (A): Water droplets form on the outer surface of a glass containing ice-cold water.
Reason (R): Water evaporates from the glass and condenses on the outside.
Reason (R): Water evaporates from the glass and condenses on the outside.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
Elite Coaching Classes answered |
- Assertion (A) is true: Water droplets form on the outer surface of a glass containing ice-cold water because the cold temperature of the glass causes moisture in the air to condense.
- Reason (R) is false: Water does not evaporate from the glass and condense on the outside. Instead, the moisture in the surrounding air condenses on the cooler surface of the glass.
- Therefore, the correct option is C: The assertion is true, but the reason is false.
- Reason (R) is false: Water does not evaporate from the glass and condense on the outside. Instead, the moisture in the surrounding air condenses on the cooler surface of the glass.
- Therefore, the correct option is C: The assertion is true, but the reason is false.
Can you explain the answer of this question below:Which property of a gas helps to fill a large volume of liquefied petroleum gas (LPG) in cylinders?
- A:
High fluidity
- B:
Low density
- C:
High inflammability
- D:
High compressibility
The answer is d.
Which property of a gas helps to fill a large volume of liquefied petroleum gas (LPG) in cylinders?
High fluidity
Low density
High inflammability
High compressibility
|
|
Aashi answered |
The correct answer is D. Because gas has high compressibility....
The boiling point of alcohol in Kelvin scale is 351K. What will be its boiling point in Celsius scale?- a)151°C
- b)251°C
- c)78°C
- d)178°C
Correct answer is 'C'. Can you explain this answer ?
The boiling point of alcohol in Kelvin scale is 351K. What will be its boiling point in Celsius scale?
a)
151°C
b)
251°C
c)
78°C
d)
178°C
|
Divya Ahuja answered |
The relationship between Kelvin scale and Celsius scale of temperature can be written as :Temperature on kelvin scale = Temperature on Celsius scale + 273
SOLUTION :
GIVEN: Boiling point of alcohol : 351 K
Temperature on kelvin scale = Temperature on Celsius scale + 273
Temperature on celsius scale = 351 - 273
Temperature on kelvin scale = 78 degree celsius
Hence, temperature of 78 deg C on Celsius scale is equal to 351 K on the Kelvin scale.
Solids do not flow because - a)of large molecular space between particles
- b)they do not have definite shape
- c)they have very strong intermolecular forces in between particles
- d)all of these
Correct answer is option 'C'. Can you explain this answer?
Solids do not flow because
a)
of large molecular space between particles
b)
they do not have definite shape
c)
they have very strong intermolecular forces in between particles
d)
all of these
|
Moumita Mishra answered |
Any thing flows due to weaker intermolecular forces between them.
Which of the following is correct order of forces of attraction?- a)Water > Air > Sand
- b)Air > Sugar > Oil
- c)Air < Water < Sugar
- d)Salt > Air > Juice
Correct answer is option 'C'. Can you explain this answer?
Which of the following is correct order of forces of attraction?
a)
Water > Air > Sand
b)
Air > Sugar > Oil
c)
Air < Water < Sugar
d)
Salt > Air > Juice
|
|
Ujwal Das answered |
B) Water is attracted to nonpolar substances, then polar substances, and finally to itself through hydrogen bonding.
What will be the state of a substance below its freezing point?- a)Plasma state
- b)Liquid state
- c)Gaseous state
- d)Solid state
Correct answer is option 'D'. Can you explain this answer?
What will be the state of a substance below its freezing point?
a)
Plasma state
b)
Liquid state
c)
Gaseous state
d)
Solid state
|
Anshika Gaharwar answered |
The temperature below the freezing point the atoms are pressurised and get attached to one another closely which provide them a fixed volume and shape that is solid.
Which factor affecting Evaporation - - a)Temperature
- b)Surface area
- c)Both (A) & (B)
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Which factor affecting Evaporation -
a)
Temperature
b)
Surface area
c)
Both (A) & (B)
d)
None of these
|
Tushar Mehta answered |
The turning of any liquid into vapour is called Evaporation. The factors affecting the evaporation are:
1. Temperature. As the temperature increases, the rate of evaporation also increases.
2. Surface Area. As the Surface area increases, the rate of evaporation increases.
3. Density. As the density increases, the rate of evaporation decreases.
4. Wind Velocity. The velocity of the wind also affects the rate of evaporation. As the velocity of wind increases, the rate of evaporation increases.
Which one of the following sets of phenomenon would increase on raising the temperature?- a)Evaporation, diffusion, compression of gases
- b)Evaporation, compression of gases, solubility
- c)Evaporation, diffusion, expansion of gases
- d)Evaporation, solubility, diffusion, compression of gases.
Correct answer is option 'C'. Can you explain this answer?
Which one of the following sets of phenomenon would increase on raising the temperature?
a)
Evaporation, diffusion, compression of gases
b)
Evaporation, compression of gases, solubility
c)
Evaporation, diffusion, expansion of gases
d)
Evaporation, solubility, diffusion, compression of gases.
|
Mihir Shah answered |
The correct answer is option 'C': Evaporation, diffusion, expansion of gases.
Explanation:
When the temperature is increased, several physical processes tend to increase. These processes include evaporation, diffusion, and expansion of gases. Let's understand each of these phenomena in detail:
1. Evaporation:
Evaporation is the process by which a liquid changes into a vapor or gas at temperatures below its boiling point. When the temperature is increased, the kinetic energy of the molecules in the liquid also increases. As a result, more molecules gain enough energy to overcome the attractive forces of the liquid and escape into the gas phase. Therefore, evaporation increases with an increase in temperature.
2. Diffusion:
Diffusion is the process of movement of particles from an area of higher concentration to an area of lower concentration. It occurs due to the random motion of particles. When the temperature is increased, the kinetic energy of the particles also increases. This increased kinetic energy leads to faster and more frequent collisions between particles, resulting in an increased rate of diffusion.
3. Expansion of gases:
When gases are heated, their molecules gain kinetic energy and move faster. This increased molecular motion leads to an increase in the volume of the gas because the molecules now occupy a larger space. Therefore, gases expand when the temperature is raised.
These three phenomena - evaporation, diffusion, and expansion of gases - all increase with an increase in temperature.
Let's summarize the answer:
- Evaporation, the process by which a liquid changes into a vapor or gas, increases with an increase in temperature.
- Diffusion, the movement of particles from an area of higher concentration to an area of lower concentration, increases with an increase in temperature.
- Expansion of gases occurs when the temperature is raised, as the increased kinetic energy of the gas molecules causes them to move faster and occupy a larger volume.
Hence, the correct answer is option 'C': Evaporation, diffusion, expansion of gases.
Explanation:
When the temperature is increased, several physical processes tend to increase. These processes include evaporation, diffusion, and expansion of gases. Let's understand each of these phenomena in detail:
1. Evaporation:
Evaporation is the process by which a liquid changes into a vapor or gas at temperatures below its boiling point. When the temperature is increased, the kinetic energy of the molecules in the liquid also increases. As a result, more molecules gain enough energy to overcome the attractive forces of the liquid and escape into the gas phase. Therefore, evaporation increases with an increase in temperature.
2. Diffusion:
Diffusion is the process of movement of particles from an area of higher concentration to an area of lower concentration. It occurs due to the random motion of particles. When the temperature is increased, the kinetic energy of the particles also increases. This increased kinetic energy leads to faster and more frequent collisions between particles, resulting in an increased rate of diffusion.
3. Expansion of gases:
When gases are heated, their molecules gain kinetic energy and move faster. This increased molecular motion leads to an increase in the volume of the gas because the molecules now occupy a larger space. Therefore, gases expand when the temperature is raised.
These three phenomena - evaporation, diffusion, and expansion of gases - all increase with an increase in temperature.
Let's summarize the answer:
- Evaporation, the process by which a liquid changes into a vapor or gas, increases with an increase in temperature.
- Diffusion, the movement of particles from an area of higher concentration to an area of lower concentration, increases with an increase in temperature.
- Expansion of gases occurs when the temperature is raised, as the increased kinetic energy of the gas molecules causes them to move faster and occupy a larger volume.
Hence, the correct answer is option 'C': Evaporation, diffusion, expansion of gases.
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