Ncert – class 9- science – Chapter 1 – Matter in Our Surroundings 1 Welcome to your Ncert - class 9- science - Chapter 1 – Matter in Our Surroundings 1 1. Which of the following is a correct statement? There is no inter-particle force of attraction between the molecules in a liquid. The inter-particle force of attraction between the molecules in a liquid is more when compared to solids. The inter-particle force of attraction between the molecules in a liquid is less when compared to solids. The inter-particle force of attraction between the molecules in a liquid is either more or less when compared to solids. None 2. The heat gained or lost during a change of state from solid to liquid or from liquid to solid is called the latent heat of ....... freezing vaporisation fusion condensation None 3. The molecules: in a solid move freely within its boundary. in a gas move only within its boundary. in a liquid move within its boundary. in solid, liquid and gas move freely anywhere. None 4. The process by which molecules undergo a spontaneous transition from the liquid phase to the gaseous phase is called as: sublimation freezing evaporation condensation None 5. Select the correct alternativeThe molecules can move freely anywhere in_____ state. liquid gaseous none of the above solid None 6. During change of state of matter, the temperature remains the same due to: loss of heat latent heat less supply of heat lattice energy None 7. Identify the correct statement about gases: Gases have definite shapes. Gases can not be compressed easily. Gases can not flow. Gases occupy the entire space of the container. None 8. A fully inflated balloon goes higher in the atmosphere, so what will be the pressure outside and inside the balloon respectively. Increases, Decreases Increases, Remains constant Decreases, Increases Decreases, Remains constant None 9. Evaporative cooling is the phenomenon _____________. none of these in which molecule of liquid with high kinetic energy evaporates quickly, leaving behind the particle of less kinetic energy in which molecule of liquid with low kinetic energy evaporates quickly, leaving behind the particle of high kinetic energy in which density of liquid changes None 10. Which among the following have moderate intermolecular forces? Gases Equal in liquids and gases both Liquids Solids None 11. Latent heat is evolved during the transformation of liquids into solids. How will you explain this statements? Heat does not get absorbed nor released None of the above Heat is absorbed and temperature increases Heat is released and temperature decreases None 12. What is the effect on the chemical and physical properties of water when the temperature is changed? The chemical properties of water change with temperature change but physical properties remain the same. Both chemical and physical properties of water change with a temperature change. The chemical properties of water remain the same but the physical state changes with a temperature change. There is no effect on the chemical or physical properties of water when the temperature is changed. None 13. Match Column I with Column II and select the correct option from the codes given belowColumn IColumn II(a) Drying of clothes on a windy day(i) Time taken for evaporation increases(b) Liquefaction of gases(ii) Decreasing pressure and increasing temperature(c) Change in state of dry ice from solid to gas(iii) Increasing pressure and decreasing temperature(d) Less cooling effect of sweating in coastal areas(iv) Rate of evaporation increases a - (i), b - (ii), c - (iii), d - (iv) a - (iv), b - (iii), c - (i), d - (ii) a - (iii), b - (iv), c - (ii), d - (i) a - (iv), b - (iii), c - (ii), d - (i) None 14. Which of the following is the BEST indicator of the actual amount of water vapour in the air? Relative humidity Dew point temperature Saturation vapour pressure Air temperature None 15. Which one of the following statement is correct in respect of fluids? Gases and solids behave as fluids Only liquids behave as fluids Only gases behave as fluids Gases and liquid behave as fluids None 16. Evaporation of a liquid takes place at: a fixed temperature higher than its boiling point. a fixed temperature and pressure. any temperature lower than its boiling point. all temperatures. None 17. The percentage of para hydrogen in ordinary hydrogen increases when? None Pressure is increased and temperature is decreased Temperature is lowered Temperature is increased None 18. Statement I : Evaporation causes cooling.Statement II: Particles of liquid absorb energy from the surrounding to regain the energy lost during evaporation. Statement I is true and statement II is false. Both statements I and II are true, statement II is not the correct explanation for statement I. Both statements I and II are true, statement II is correct explanation for statement I. Statement I is false and statement II is true. None 19. The temperature of melting ice remains constant for some time even if we continue to supply heat to the beaker. This is because of the heat energy ? is used to bring the particles of matter closer is used to change the pressure on the particles is used to overcome the forces of attraction between the particles is radiated out None 20. Which one of the following statement is correct ? Boiling is a bulk phenomenon, but evaporation is a surface phenomenon Both boiling and evaporation are bulk phenomena. Both boiling and evaporation are surface phenomena. Boiling is a surface phenomenon, but evaporation is a bulk phenomenon None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
