Question:
Why do diffusion become faster at higher temperatures?
Answer:
The speed of particles in any form of matter increases with the rise in temperature. Hence the reason.
Matter in Our Surroundings
Q 1.
What is SI unit of temperature? Give mathematical relation also.
Q 3.
What do you mean by change in state?
Q 4.
How matter is classified in terms of physical state?
Q 5.
What is evaporation? Why does evaporation cause cooling?
Q 6.
What do you mean by the term Volume?
Q 7.
Which state of matter is most easily compressible?
Q 8.
What are the ways a gas can be liquefied?
Q 9.
List any five physical properties of liquids.
Q 10.
Define the term Volatile Liquid.
Q 11.
Define transpiration.
Q 12.
Arrange the following substances in increasing order of intermolecular force of attraction: water, sugar, oxygen
Q 13.
Why solids cannot be compressed like gases?
Q 15.
How matter is classified in terms of composition?
Q 16.
The mass per unit volume of a substance is called density (density=mass/volume). Arrange the following in order of increasing density:
Air, Exhaust from chimneys, Honey, Water, Chalk, Cotton and Iron.
Q 17.
Define evaporation.
Q 18.
What are the differences between boiling and evaporation?
Q 19.
Our own bodies contain examples of all three states of matter. Can you identify these?
Q 20.
What do you mean by the following terms:
a. Evaporation
b. Sublimation
c. Condensation
Q 21.
Define Latent Heat of Fusion and Latent Heat of vaporisation.
Q 22.
Why is light not considered matter?
Q 23.
Why do diffusion become faster at higher temperatures?
Q 24.
How can matter change its state?
Q 25.
How vapour is different from gases? Give examples of each.
Q 26.
Which of the following are matter?
Chair, Air, Love, Smell, Hate, Almonds, Thought, Cold, Cold drinks, Smell of perfume
Q 27.
In which case evaporation of water will be faster i.e. near the sea or far away from the sea.
Q 28.
What is the physical state of water at the following temperatures? (a) 25 °C (b) 0 °C (c) 100 °C
Q 29.
Convert the following temperature to Celsius scale: (a) 300 K (b) 573 K
Q 30.
Explain compressibility in gases with an example?
Q 31.
Which of the following state does not exist at room temperature conditions: a) Solids b) Liquids c) Gas d) Plasma
Q 32.
Why does the temperature of a substance remain constant during melting and boiling even when heat is being supplied to it continuously?
Q 33.
Why do gases diffuse rapidly?
Q 34.
Define the following terms:
a. Melting point
b. Freezing point
c. Boiling point
Q 35.
Why is ice at 273 K more effective in cooling than water at the same temperature?
Q 36.
The Kelvin scale temperature is 0 K. What is the corresponding Celsius scale temperature ?
Q 37.
What factors affect the rate of evaporation?
Q 38.
Give reasons for the following observations. The smell of hot sizzling food reaches you several meters away, but to get smell from cold food you have to go close.
Q 39.
Explain with an experiment to show gases do not have fixed shape or volume.
Q 40.
Name the process by which a drop of ink spreads in a beaker of water.
Q 41.
What are the characteristics of matter?
Q 42.
Differences among solids, liquids and gases.
Q 43.
Write the relation between Kelvin scale and Celsius scale of temperature.
Q 44.
The boiling point of water is 100°C. Express this in SI units (Kelvin scale).
Q 45.
What is the (a) common unit of temperature, and (b) SI unit of temperature ?
Q 46.
(a) Define the term 'latent heat of vaporisation' of a liquid. What is the value of the latent heat of vaporisation of water ?
(b) Draw a labelled diagram of the experimental set-up to study the latent heat of vaporisation of water.
Q 47.
A diver is able to cut through water in a swimming pool. Which property of matter does this observation show?
Q 48.
Give reasons to justify: (a) Water at room temperature is a liquid. (b) An iron almirah is solid.
Q 49.
Is smell of garlic or perfume a matter?
Q 50.
The Kelvin temperature is 270 K. What is the corresponding Celsius scale temperature ?
