Everything around us is made up of matter. This lesson explains the nature of particles, their arrangement, movement and how matter changes its state due to temperature and pressure. Concepts like diffusion, evaporation, sublimation, melting, boiling and condensation are generally asked in NIOS examinations through MCQs, short answers, activities and case studies.
The questions below are prepared from the lesson Matter in Our Surroundings and NIOS exam pattern to help you practice all important concepts in one place. This post covers all important questions with exam ready answers as per NIOS pattern.
NIOS Class 10 Science Chapter 2
MCQs with Answers
Q1. Matter is anything that has:
(a) Colour
(b) Mass and volume
(c) Smell
(d) Shape
Correct answer – (b) Mass and volume
Q2. The particles of matter are:
(a) At rest
(b) Very large
(c) Continuously moving
(d) Visible
Correct answer – (c) Continuously moving
Q3. In which state ofmatter do particles mix most rapidly with each other?
(a) Solid state
(b) Liquid state
(c) Gaseous state
(d) Semi solid state
Correct answer – (c) Gaseous state
Q4. In which substance is the distance between particles the greatest?
(a) Ice
(b) Water
(c) Air
(d) Salt solution
Correct answer – (c) Air
Q5. In which state are particles held together most tightly?
(a) Gas
(b) Liquid
(c) Solid
(d) Vapour
Correct answer – (c) Solid
Q6. What is the name of process when a solid changes directly into vapour?
(a) Fusion
(b) Condensation
(c) Sublimation
(d) Evaporation
Correct answer – (c) Sublimation
Q7. Why does camphor gradually disappear when left open?
(a) It melts into liquid
(b) It directly changes into vapour
(c) It reacts with air
(d) It dissolves in moisture
Correct answer – (b) It directly changes into vapour
Q8. At what temperature can evaporation take place?
(a) Only at boiling point
(b) Only at freezing point
(c) At any temperature
(d) At 100º C
Correct answer – (c) At any temperature
Q9. Which process converts liquid into vapour without heating it to boiling point?
(a) Boiling
(b) Evaporation
(c) Freezing
(d) Deposition
Correct answer – (b) Evaporation
Q10. Rise in temperature affects particles by increasing their:
(a) Size
(b) Attraction
(c) Kinetic energy
(d) Weight
Correct answer – (c) Kinetic energy
Q11. At what temperature does ice start turn into water?
(a) 100ºC
(b) 0ºC
(c) 273ºC
(d) -100ºC
Correct answer – (b) 0ºC
Q12. Water starts boiling and converting into steam at:
(a) 80º C
(b) 90º C
(c) 100º C
(d) 120º C
Correct answer – 100º C
Q13. What do we call the conversion of vapour into liquid form?
(a) Evaporation
(b) Melting
(c) Condensation
(d) Freezing
Correct answer – (c) Condensation
Q14. The phenomenon of diffusion shows that particles:
(a) Possess colour
(b) Remain stationary
(c) Are continuously moving
(d) Are large in size
Correct answer – (c) Are continuously moving
Q15. Which state has definite shape as well as definite volume?
(a) Liquid
(b) Gas
(c) Solid
(d) Vapour
Correct answer – (c) Solid
Q16. Identify the state which has fixed volume but takes the shape of its container.
(a) Solid
(b) Liquid
(c) Gas
(d) Plasma
Correct answer – (b) Liquid
Q17. Which state can be easily compressed due to large space between particles?
(a) Solid
(b) Liquid
(c) Gas
(d) Ice
Correct answer – (c) Gas
Q18. What effect does evaporation produce on the surroundings?
(a) Heating effect
(b) Cooling effect
(c) Freezing effect
(d) Melting effect
Correct answer – (b) Cooling effect
Q19. Why do wet clothes dry when spread in open air?
(a) Condensation
(b) Sublimation
(c) Evaporation
(d) Diffusion
Correct answer – (c) Evaporation
Q20. The speeding of perfume smell in a room is due to:
(a) Evaporation
(b) Diffusion
(c) Sublimation
(d) Condensation
Correct answer – (b) Diffusion
Q21. Latent heat is associate with:
(a) Increase in temperature
(b) Decrease in temperature
(c) Change in physical state
(d) Expansion of gas
Correct answer – (c) Change in physical state
Q22. Applying high pressure on a gas can convert it into:
(a) Solid
(b) Liquid
(c) Vapour
(d) None of these
Correct answer – (b) Liquid
Q23. What is the term for conversion of gas directly into solid?
(a) Fusion
(b) Deposition
(c) Evaporation
(d) Condensation
Correct answer – (b) Deposition
Q24. The reason particles remain together in matter is:
(a) Magnetism
(b) Force of attraction
(c) Heat energy
(d) Gravity
Correct answer – (b) Force of attraction
Q25. In how many physical states is matter commonly found?
(a) Two
(b) Four
(c) Three
(d) Five
Correct answer – (c) Three
Very Short Answer Type Questions
Q1. Why does the smell of food spread quickly in a room?
Answer
The smell spreads due to diffusion. Gas particles move randomly and mix with air, allowing smell to travel quickly throughout the room.
Q2. Why can a solid not be compressed easily?
Answer
In solids, particles are very closely packed with strong intramolecular forces and very little space between them, making compression difficult.
Q3. What is sublimation?
Answer
Sublimation is the direct change of solid into gas
without passing through the liquid state.
Q4. Why do we feel cool when we apply spirit or perfume on our skin?
Answer
Spirit of perfume evaporates quickly by absorbing heat from the skin which produces a cooling effect.
Q5. Why doe ice float on water?
Answer
Ice has more space between its particles compared to water, making it less dense so it floats on water surface.
Q6. Why are gases highly compressible?
Answer
Gases have very large spaces between particles and very weak force of attraction which allow them to be compressed easily.
Q7. What is condensation?
Answer
Condensation is the change of vapour into liquid on cooling.
Q8. Why does camphor reduce in size when left open?
Answer
Camphor undergoes sublimation and directly changes from solid to vapour which causing reduce in size .
Q9. What is latent heat?
Answer
Latent heat is the heat absorbed or released during change of state without change in temperature.
Q10. Why do gases fill the container completely?
Answer
Gas particles have very weak intermolecular forces between them so they move freely and fill the container completely.
Short AnswerTypes Questions
Q1. Describe characteristics of particles of matter.
Answer
Particles of matter have following characteristics:
i. They are very small.
ii. They have spaces between them.
iii. They are in continuous motion.
iv. They attract each other.
Q2. Explain why diffusion is faster in gases than liquids.
Answer
In gases, particles have maximum space and very weak forces of attraction. They move freely at high-speed allowing faster intermixing. In liquids particles are closer and move slowly, so diffusion occurs slowly.
Q3. Differentiate evaporation and boiling.
Answer
|
Evaporation |
Boiling |
|
It occurs at any temperature from the surface of the liquid. |
It occurs at fixed temperature throughout the liquid. |
|
It is slow process. |
It is rapid process. |
Q4. How does evaporation cause cooling?
Answer
During evaporation, high energy particles escape from the liquid surface by absorbing heat form surroundings. This lowers the average kinetic energy of remaining particles and produce cooling effect.
Q5. Explain the effect of temperature on state of matter.
Answer
When temperature increase, the kinetic energy of particles also increases. This weakens the force of attraction between particles; this leads to change of solid into
liquid and liquid into gas. Decrease in temperature has reverse effect.
Q6. How can pressure change the state of gases?
Answer
When high pressure is applied on gas, its particles come closer to each other and gas change into liquid.
Long Answer Type Questions
Q1. Explain three states of matter with properties.
Answer
Matter exists in three physical states: solid, liquid and gas. These states differ because of the arrangement of particles, space between them and force of attraction between them.
Solids have a definite shape and definite volume. The particles are very closely packed with very strong intermolecular forces. They can only vibrate at their fixed positions which makes solids rigid and incompressible. Examples: iron, wood, ice.
Liquids have a definite volume but not definite shape. The particles are close but can slide over one another due to moderate fore of attraction. This allows liquids to flow and take the shape of the container.
Examples: water, milk, oil.
Gases have neither definite shape nor definite volume. The particles are far apart with very weak forces of attraction and move freely in all directions. This is why gases can be compressed easily and fill the entire container. Examples: air, oxygen, carbon dioxide.
Q2. Explain change of states of matter with diagram.
Answer
Matter can change from one state to another by changing temperature or pressure. These changes occur because the kinetic energy of particles and the force of attraction between them vary.
When a solid is heated, its particles gain kinetic energy and start vibrating faster. At a certain temperature (melting point), the fore of attraction weakens and the solid changes into a liquid. This process is called melting. When the liquid is cooled, it changes back into solid, called freezing.
On further heating, the liquid particles gain more energy and at the boiling point, they escape into the air as gas. This is called boiling or vaporisation. When gas is cooled, it loses energy and changes back into liquid. This process is condensation.
Some substances like camphor change directly from solid to gas without becoming liquid. This is called sublimation. The reverse process (gas to solid) is called deposition.
Q3. What is latent heat of fusion and vaporisation?
Answer
During a change of state, matter absorbs heat energy but its temperature does not rise. This hidden heat energy is called latent heat.
Latent heat of fusion:
The amount of heat required to convert a solid into liquid at its melting point without any change in temperature. For example: ice at 0º C changes into water at 0º C by absorbing latent heat of fusion.
Latent heat of vaporisation:
The amount of heat required to convert a liquid into vapour at its boiling point without any change in temperature. For example: water at 100º C changes into steam at 100º C by absorbing latent heat of vaporisation.
In both cases. The heat energy is used to overcome the force of attraction between particles rather than increasing temperature.
Q4. Explain factors affecting evaporation.
Answer
Evaporation is the slow conversion of a liquid into vapour from its surface at any temperature. The rate of evaporation depends on following factors:
Temperature:
Higher temperature increases the kinetic energy of particles, so they escape into vapour.
Surface area:
A larger surface area exposes more particles to the air, this increase evaporation rate.
Humidity: Ehen the air already contains a large amount of water vapour, it slows down the evaporation. In dry air, evaporation is faster.
Wind speed:
Fast wind removes the vapour particles form the surface of liquid and allow more evaporation.
These factors affect evaporation.
Diagram Based Questions
Q1. Draw a labelled diagram to show arrangements of particles in different states of matter.
Answer
Q2. Draw a labelled diagram showing effect of pressure on liquid and gas.
Answer
Q3. Draw a labelled diagram showing separation by using Separating Funnels.
Answer
Q4.Draw a labelled diagram showing separation by Distillation.
Answer
Case Study based Question
Read the passage and answer the questions
On a hot summer day, Meena sprinkled water on floor of her room. After some time, the floor became dry and she felt a cooling effect in the room. She also notices that the smell of perfume sprayed in one corner spread quickly throughout the room. Later she placed some camphor on a plate and observed that it gradually reduced in size without leaving any liquid behind.
Q1. Which process is responsible for drying of the wet floor?
Answer
Evaporation is the process responsible for it.
Q2. Why did Meena feel a cooling effect after sprinkling water?
Answer
During evaporation, water absorbs heat from the surroundings, causing a cooling effect.
Q3. What is the process by which camphor reduces in size without forming liquid?
Answer
Sublimation
Q4. State one factor that increase the rate of drying of the floor.
Answer
Increase in temperature or wind speed