Matter In Our Surroundings - Class 9 MCQ

BEC ( BOSE-EINSTEIN CONDENSATE) IS THE FIFTH STATE OF MATTER

This is because plasma consists of the most reactive ionized particles.

Largest State of Matter:
The largest state of matter refers to the state with the greatest number of particles or entities. In this case, the options provided are element, atoms, compounds, and molecules. Let's evaluate each option to determine the largest state of matter:
A: ELEMENT
- An element is a substance made up of only one type of atom.
- Elements are the building blocks of matter and cannot be broken down into simpler substances.
- While elements can exist as individual particles, they are not considered the largest state of matter.
B: ATOMS
- Atoms are the smallest units of matter that retain the properties of an element.
- Atoms can exist as individual particles or combine to form molecules or compounds.
- While atoms are fundamental to the structure of matter, they are not considered the largest state of matter.
C: COMPOUNDS
- Compounds are substances composed of two or more different elements chemically bonded together.
- Compounds can exist as individual particles or in various states (solid, liquid, gas).
- While compounds are important in the study of matter, they are not considered the largest state of matter.
D: MOLECULES
- Molecules are formed when two or more atoms are joined together by chemical bonds.
- Molecules can be composed of the same or different elements.
- Molecules can exist as individual particles or in various states (solid, liquid, gas).
- The combination of multiple molecules can form the largest state of matter.
Conclusion:
Based on the options provided, the largest state of matter is molecules. Molecules are formed by the combination of atoms and can exist as individual entities or in large quantities, making them the largest state of matter.

They have their own property. Like SO_2 ^.

Plasma is found in sun

cause the universe is still unexplored

The most common state of matter found on Earth is gas.
There are several reasons why gas is the most common state of matter on Earth:
1. Composition of the Earth's Atmosphere:
- The Earth's atmosphere is primarily composed of gases such as nitrogen (78%) and oxygen (21%).
- These gases are constantly in a gaseous state, making gas the most abundant state of matter on Earth.
2. Volatile Substances:
- Many substances found on Earth exist in a gaseous state at normal temperatures and pressures.
- Examples include water vapor, carbon dioxide, methane, and various pollutants.
- These gases are released into the atmosphere through natural processes such as evaporation, respiration, and volcanic activity.
3. Weather and Climate:
- Weather phenomena such as wind, clouds, and rain are all associated with the gaseous state of matter.
- The water cycle involves the constant conversion of water between its liquid and gaseous states.
- The movement and interaction of gases in the atmosphere play a significant role in shaping Earth's climate.
4. Human Activities:
- Human activities also contribute to the presence of gases on Earth.
- Industrial processes, transportation, and energy production release gases such as carbon dioxide, sulfur dioxide, and nitrogen oxides into the atmosphere.
In summary, while solids and liquids are also present on Earth, gas is the most common state of matter due to the composition of the Earth's atmosphere, the presence of volatile substances, weather and climate phenomena, and human activities.

Introduction:
When common salt (sodium chloride) is dissolved in water at a specific temperature, certain changes occur. Let's explore what happens when we dissolve common salt in water at 30°C.
Key Points:
- When common salt (sodium chloride) is dissolved in water at 30°C, the level of water will not change.
- This is because dissolving common salt in water does not result in a change in the volume of the solution.
- The dissolved salt particles mix uniformly with the water molecules, but the total volume of the solution remains the same.
- The salt dissolves due to the attractive forces between the water molecules (solvent) and the salt particles (solute).
- At 30°C, the solubility of common salt in water is relatively high, meaning a significant amount of salt can dissolve in water at this temperature.
Conclusion:
When common salt is dissolved in water at 30°C, the level of water remains unchanged. The dissolved salt particles mix evenly with the water molecules, but the overall volume of the solution remains the same.

Process of Separating Water into Hydrogen and Oxygen: Electrolysis
To separate water into hydrogen and oxygen, the process of electrolysis is used. Electrolysis involves the use of an electric current to drive a non-spontaneous chemical reaction. Here is a detailed explanation of the process:
1. Set up the electrolysis apparatus:
- A source of direct current (DC) power, such as a battery or power supply, is connected to two electrodes.
- The electrodes are typically made of inert materials like platinum or graphite.
- The electrodes are immersed in a container filled with water, which acts as the electrolyte.
2. Electrolysis occurs:
- When the electric current is turned on, it flows through the water and causes a chemical reaction.
- The positive electrode, called the anode, attracts negatively charged ions (anions), such as hydroxide ions (OH-).
- At the anode, water molecules lose electrons and undergo oxidation, generating oxygen gas (O2).
3. Formation of hydrogen gas:
- The negative electrode, called the cathode, attracts positively charged ions (cations), such as hydrogen ions (H+).
- At the cathode, water molecules gain electrons and undergo reduction, producing hydrogen gas (H2).
- The hydrogen gas bubbles up at the cathode, while the oxygen gas is released at the anode.
4. Collection of the gases:
- The hydrogen and oxygen gases can be collected separately by using gas collection tubes or other appropriate methods.
- The gases can be tested for purity and properties, such as flammability for hydrogen and supporting combustion for oxygen.
5. Overall reaction:
- The overall reaction for the electrolysis of water can be represented as:
2H2O(l) -> 2H2(g) + O2(g)
6. Applications:
- The separated hydrogen and oxygen gases have various practical applications, such as fuel cells, welding, and chemical synthesis.
In summary, the process of separating water into hydrogen and oxygen involves the use of electrolysis, which utilizes an electric current to break down water molecules into their constituent gases.

What is matter?
Matter is anything that has mass and takes up space. It is the physical substance that makes up the universe and everything in it. Matter can exist in various forms such as solid, liquid, gas, and plasma. Here is a detailed explanation of the characteristics of matter:
1. Occupies space:
- Matter occupies physical space and has a definite volume and shape.
- It cannot exist in the same space as another object simultaneously.
2. Has weight:
- Matter has mass, which is a measure of the amount of matter in an object.
- Mass gives rise to the force of gravity, which results in weight.
- Weight is the measure of the gravitational force exerted on an object.
3. Can be felt:
- Matter can be sensed or felt through our senses.
- We can feel the texture, temperature, and pressure of different forms of matter.
4. All of the above:
- All the characteristics mentioned above are true for matter.
- Matter occupies space, has weight, and can be felt.
In conclusion, matter is a fundamental component of the universe that occupies space, has weight, and can be felt. It exists in various forms and is essential for the existence of all physical objects.