All questions of Cycling of Matter for Grade 9 Exam
The correct relationship between picometer and nanometer is- a)1nm = 1000pm
- b)1nm = 10pm
- c)1pm = 10nm
- d)1pm = 100nm
Correct answer is option 'A'. Can you explain this answer?
The correct relationship between picometer and nanometer is
a)
1nm = 1000pm
b)
1nm = 10pm
c)
1pm = 10nm
d)
1pm = 100nm
|
Neha Joshi answered |
1 picometer = 10-12 m
1 nanometer=10-9 m
So, 1 picometer = 0.001 nanometer .
From this we get 1 nanometer= 1000 picometer.
1 nanometer=10-9 m
So, 1 picometer = 0.001 nanometer .
From this we get 1 nanometer= 1000 picometer.
Hence, the correct answer is Option A.
Which one of the following is not a mixture?- a)Distilled water
- b)Sugar dissolved in water
- c)Liquefied Petroleum Gas (LPG)
- d)Gasoline
Correct answer is option 'A'. Can you explain this answer?
Which one of the following is not a mixture?
a)
Distilled water
b)
Sugar dissolved in water
c)
Liquefied Petroleum Gas (LPG)
d)
Gasoline
|
Gaurav Kumar answered |
Distilled water is the pure form of water with no impurities present in it; others are the mixture of two or more components.
Which of the following is an element?- a)Sugar solution
- b)Brass
- c)HCl
- d)Copper metal
Correct answer is option 'D'. Can you explain this answer?
Which of the following is an element?
a)
Sugar solution
b)
Brass
c)
HCl
d)
Copper metal
|
Krishna Iyer answered |
Copper is a chemical element with symbol Cu and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity.
One sample of air is found to have 0.03% carbon dioxide and another sample 0.02%. This illustrates that:- a)Air is a compound
- b)Air is an element
- c)Air does not follow the law of constant proportions
- d)Air is a mixture
Correct answer is option 'D'. Can you explain this answer?
One sample of air is found to have 0.03% carbon dioxide and another sample 0.02%. This illustrates that:
a)
Air is a compound
b)
Air is an element
c)
Air does not follow the law of constant proportions
d)
Air is a mixture
|
Raghav Bansal answered |
Air is a mixture.
When we combine more than one type of element, known as a mixture.
The different percentages are showing that these other elements are present.
When we combine more than one type of element, known as a mixture.
The different percentages are showing that these other elements are present.
A pure substance can only be:- a)A compound
- b)An element
- c)An element or a compound
- d)A heterogeneous mixture
Correct answer is option 'C'. Can you explain this answer?
A pure substance can only be:
a)
A compound
b)
An element
c)
An element or a compound
d)
A heterogeneous mixture
|
Pooja Shah answered |
A pure substance is a substance in which only one type of atom or molecule is present.
Example: Water, Sulphur, Sucrose(pure), Helium, etc.
Thus, a pure substance can only be an element or a compound.
Example: Water, Sulphur, Sucrose(pure), Helium, etc.
Thus, a pure substance can only be an element or a compound.
Formula mass is used for which of the following substances?- a)Ionic compounds
- b)Molecules
- c)Atoms
- d)Molecular compounds
Correct answer is option 'A'. Can you explain this answer?
Formula mass is used for which of the following substances?
a)
Ionic compounds
b)
Molecules
c)
Atoms
d)
Molecular compounds
|
|
Mayank Chatterjee answered |
Formula mass is used for ionic compounds. Because ionic compounds don't exist as individual molecules hence we take simplest ratio of elements present in that compound so we can't take it as molecular mass. Hence separate name formula mass is given. For example formula mass of NaCl is 23+35.5=58.5
Which of the following is a compound?- a)Air
- b)Gold
- c)Water
- d)Sulphur
Correct answer is option 'C'. Can you explain this answer?
Which of the following is a compound?
a)
Air
b)
Gold
c)
Water
d)
Sulphur
|
|
Jeshika Maurya answered |
Water is a compound...
H2O made of more than 1 element hydrogen and oxygen so its compound...
H2O made of more than 1 element hydrogen and oxygen so its compound...
Substances whose two or more components completely mix with each other to make a uniform composition are called:- a)Ionic compounds
- b)Elements
- c)Heterogeneous mixtures
- d)Homogeneous mixtures
Correct answer is option 'D'. Can you explain this answer?
Substances whose two or more components completely mix with each other to make a uniform composition are called:
a)
Ionic compounds
b)
Elements
c)
Heterogeneous mixtures
d)
Homogeneous mixtures
|
|
Anand Kapoor answered |
Homogeneous Mixture: Mixtures having a uniform composition throughout their body are called Homogeneous Mixtures.
For example: a mixture of salt and water, a mixture of sugar and water, air, lemonade, soda water, etc. Here, a mixture of salt in water is a classic example. This is because here, the boundary, between salt and water can never be differentiated. When a ray of light is passed through the mixture of salt and water, the path of light is not seen.
For example: a mixture of salt and water, a mixture of sugar and water, air, lemonade, soda water, etc. Here, a mixture of salt in water is a classic example. This is because here, the boundary, between salt and water can never be differentiated. When a ray of light is passed through the mixture of salt and water, the path of light is not seen.
Which of the following is a characteristic property of both mixtures and compounds?- a)Their properties are same as those of their components
- b)Energy is released when they are formed
- c)Their masses are equal to the sum of the masses of their components
- d)They contain the components in fixed proportions
Correct answer is option 'C'. Can you explain this answer?
Which of the following is a characteristic property of both mixtures and compounds?
a)
Their properties are same as those of their components
b)
Energy is released when they are formed
c)
Their masses are equal to the sum of the masses of their components
d)
They contain the components in fixed proportions
|
Jyoti Dey answered |
Mixture and a compound both follow the law of conservation of mass so their weight equals the sum of the weights of their components.
A compound is a substance made up of two or more elements chemically combined in a fixed proportion by mass. And also compound is formed as a result of chemical reaction between the constituent elements.
Arsenic is a/an:- a)Element
- b)Heterogeneous mixture
- c)Homogeneous mixture
- d)Compound
Correct answer is option 'A'. Can you explain this answer?
Arsenic is a/an:
a)
Element
b)
Heterogeneous mixture
c)
Homogeneous mixture
d)
Compound
|
Harshitha Mehta answered |
Arsenic is a chemical element with symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but only the gray form, which has a metallic appearance, is important to industry.
Chapter doubts & questions for Cycling of Matter - Biology 2025 is part of Grade 9 exam preparation. The chapters have been prepared according to the Grade 9 exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for Grade 9 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
Chapter doubts & questions of Cycling of Matter - Biology in English & Hindi are available as part of Grade 9 exam.
Download more important topics, notes, lectures and mock test series for Grade 9 Exam by signing up for free.
Biology
153 videos|283 docs|127 tests
|
|
© EduRev
|
Education Revolution
|
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup