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Mayank1444
@mayank1444
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Joined: Oct 11, 2021
Last seen: Nov 14, 2021
Topics: 0 / Replies: 2157
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Answer to: Explain why: (a) Air is used to inflate tyres. (b) Steel is used to make railway lines.

(a) When air is blown the particles in air pushes the tyre walls from inside and exerts a pressure on them. (b) Steel is used to make railway lines...

4 years ago
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Answer to: Honey is more viscous then water. Can you suggest why?

Honey is more viscous than water because the force of attraction between the particles of honey is much more than that of the force of attraction of p...

4 years ago
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Answer to: When a crystal of copper sulphate is placed at the bottom of a beaker containing water, the water slowly turns blue. why?

When a crystal of copper sulphate is placed at the bottom of a beaker containing water, the water slowly turns blue because of the diffusion of copper...

4 years ago
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Answer to: Explain why, when a bottle of perfume is opened in a room, we can smell it even from a considerable distance.

The particles of perfume start diffusing around the air and moves from lower concentration by virtue of their kinetic energy.

4 years ago
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Answer to: Explain how, the smell of being cooked in the kitchen reaches us even from a considerable distance.

The smell of food being cooked reaches us even from a considerable distance is because of the process of diffusion.

4 years ago
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Answer to: Give reason of the following observation: The smell of hot sizzling food reaches us even from a considerable distance but to get the smell from cold food, we have to go close to it.

The rate of diffusion of a hot gas is faster than the cold gas. So the particles have greater kinetic energy when the gas is hot and moves faster.

4 years ago
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Answer to: What does the diffusion of gases tell us about their particles? (b) Give one example of diffusion of gases in a liquid.

(a) Diffusion of gases tells us that the matter comprises of tiny particles and has space between them. The particles of matter are in constant motion...

4 years ago
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Answer to: Give two reasons to justify that: (a) Water is a liquid at room temperature. (b) An iron almirah is a solid.

(a) (i)Water has fixed volume but no fixed shape. (ii) Water flows freely. (b) (i) The iron almirah has fixed shape and volume. (ii) Particles...

4 years ago
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Answer to: How do solid, liquids and gases differ in shape and volume?

(i) Solids – They have a fixed shape and a fixed volume. (ii) Liquids – They have a fixed volume but no fixed shape. (iii) Gases – They neither ...

4 years ago
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Answer to: Why do gases have neither a fixed shape nor a fixed volume?

Gases do not have a fixed shape or volume so that the particles are freely moving. They do not have a fixed position or spaces between them.

4 years ago
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Answer to: State two characteristic properties each of: (a) a solid (b) a liquid (c) a gas

Solid: 1. It has strong intermolecular force of attraction between particles 2. It has definite shape and volume Liquid: 1. It does not ha...

4 years ago
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Answer to: Name the three states of matter. Give one example of each.

(i) The solid state – Ice. (ii) The liquid state – Water. (iii) The gas state – Air.

4 years ago
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Answer to: Explain the following: When an incense stick is lighted in the corner of a room, its fragrance spreads quickly in the entire room.

The fragrance of incense stick spreads quickly because the particle moves continuously in all directions. Both the air and fragrance have large interm...

4 years ago
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Answer to: Which of the following diffuses fastest and which the slowest? Solid, Liquid and Gas. Give reasons for your answer.

Solids diffuse the slowest as the particles in solids do not move from their fixed positions. Gases diffuse the fastest as the particles in gases m...

4 years ago
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Answer to: Explain why, the diffusion of the solid in another solid is a very slow process.

Diffusion is a slow process in solids because the particles do not move from their fixed positions and only vibrate.

4 years ago
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Answer to: Give one example of the diffusion of a solid in another solid.

Diffusion of solid into another solid is an extremely slow process because the particles do not move from the fixed positions and they vibrate. When t...

4 years ago
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Answer to: Explain why, we can easily move our hand in air but to do the same through a plank of wood, we need a karate expert.

There will be a weak force of attraction between the particles in air. So we can move our hands on air whereas the particles in solid plank are closel...

4 years ago
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Answer to: Describe in your own words, what happens to the particles when salt dissolves in water.

Salt when dissolves in water the tiny particles occupy the spaces between the water particles and mix with them, thus gives a taste to water. There wo...

4 years ago
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