Particulate Nature of Matter — Practice

Q1. The basic units that make up a larger piece of any substance or material are called its

• A. Bulk pieces
• B. Constituent particles
• C. Visible grains
• D. Surface molecules

Q2. When a stick of chalk is broken and then ground into fine powder, the change is a

• A. Chemical change because a new substance is formed
• B. Physical change because no new substance is formed
• C. Nuclear change because particles are split
• D. Biological change because chalk decays

Q3. The spaces between the constituent particles of matter are called

• A. Inter-atomic gaps
• B. Particle voids
• C. Interparticle spaces
• D. Molecular pores

Q4. The forces that hold the constituent particles of matter together are

• A. Repulsive in nature and called interparticle repulsions
• B. Attractive in nature and called interparticle attractions
• C. Gravitational forces between particles
• D. Magnetic forces between particles

Q5. Solids are characterised by having

• A. A definite shape and a definite volume
• B. No definite shape but a definite volume
• C. No definite shape and no definite volume
• D. A definite shape but no definite volume

Q6. The minimum temperature at which a solid melts to become a liquid at atmospheric pressure is called its

• A. Boiling point
• B. Freezing point
• C. Melting point
• D. Evaporation point

Q7. According to Table 7.1 in the chapter, what is the melting point of iron?

• A. 0 °C
• B. 133 °C
• C. 538 °C
• D. 1538 °C

Q8. When water is poured from one container into a differently shaped container, it

• A. Takes the shape of the new container
• B. Keeps the shape of the first container
• C. Loses its volume completely
• D. Becomes a solid block in the corner

Q9. The temperature at which a liquid boils and turns into vapour at atmospheric pressure is called its

• A. Melting point
• B. Evaporation point
• C. Condensation point
• D. Boiling point

Q10. Gases differ from liquids and solids because gases

• A. Have a fixed shape but no fixed volume
• B. Have a fixed volume but no fixed shape
• C. Have neither a fixed shape nor a fixed volume
• D. Have both a fixed shape and a fixed volume

Q11. Both liquids and gases flow and do not retain a fixed shape. For this reason they are together classified as

• A. Solids
• B. Fluids
• C. Vapours
• D. Plasmas

Q12. When the plunger of a needle-less syringe with thumb closing the nozzle is pushed inward, the volume of air inside

• A. Stays exactly the same
• B. Increases as the plunger moves
• C. Decreases as the plunger moves
• D. Drops to zero immediately

Q13. When Activity 7.6 is repeated using water instead of air in the syringe, we observe that water is

• A. Easily compressible like air
• B. Practically incompressible
• C. Easily expandable on pushing
• D. Converted into ice on pushing

Q14. In Activity 7.8, when a grain of potassium permanganate is dropped into a glass of water without stirring, what is finally observed after some time?

• A. The grain sinks and no colour spreads at all
• B. Only the bottom layer turns dark purple
• C. The entire bulk of water acquires a uniform pink colour
• D. The water boils and gives off pink fumes

Q15. Priya lights an incense stick in one corner of the classroom. After some minutes the fragrance reaches every corner of the room. This is because

• A. The particles of air and fragrance are in constant motion and spread throughout the room
• B. Fragrance particles are repelled by air particles to the walls
• C. Air particles burn the fragrance and turn into pink smoke
• D. Fragrance particles change into water vapour and condense everywhere