B. FILL IN THE BLANKS :
and
1. The three states of matter are
energy
2. When a gas is cooled its molecules
3. Molecules are compactly arranged in
4. The position of molecules in a solid is
5.
molecules move freely in all directions.
6. Air has
and occupies...
7. Intermolecular forces of attraction are least in
Answers
Answer:
Question 1:
What are the conditions for 'something' to be called 'matter'?
ANSWER:
The main conditions for something to be matter are, it should:
(a) occupy space and
(b) have mass
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Question 2:
Name two processes which provide the best evidence for the motion of particles in matter.
ANSWER:
Diffusion and Brownian motion, provide the best evidence about the random motion of particles in matter.
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Question 3:
Which single term is used to describe the mixing of copper sulphate and water kept in a beaker, on its own?
ANSWER:
Diffusion is the single term, which is used to describe the mixing of copper sulphate with water in a beaker on its own.
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Question 4:
When sugar is dissolved in water, there is no increase in the volume. Which characteristic of matter is illustrated by this observation?
ANSWER:
The absence of increase in volume of water on dissolution of sugar into it, describes the following characteristics of matter:
(a) Matter is made up of very, very small particles.
(b) Particles of matter have spaces between them.
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Question 5:
Even two or three crystals of potassium permanganate can impart colour to a very large volume of water. Which characteristic of particles of matter is illustrated by this observation?
ANSWER:
When crystals of potassium permanganate are placed at the bottom of a beaker of water, water in the whole beaker turns pink on its own. This process represents that matter is made up of smal