MCQ with Answers : Matter In Our Surroundings Chapter 1 Science Class 9 Chemistry
1. Which of the following phenomena would increase on raising the temperature ?
(i) Diffusion, evaporation, compression of gases
(ii) Evaporation, compression of gases, solubility
(iii) Evaporation, diffusion, expansion of gases
(iv) Evaporation, solubility, diffusion, compression of gases
(ii) Evaporation, compression of gases, solubility
(iii) Evaporation, diffusion, expansion of gases
(iv) Evaporation, solubility, diffusion, compression of gases
Answer:
(iii) Evaporation, diffusion, expansion of gases
2. Chanda visited a Natural Gas Compressing unit and found that the gas can be liquified under specific conditions of temperature and pressure. While sharing her experience with friends she got confused. Help her to idetify the correct set of conditions.
(i) Low temperature, low pressure
(ii) High temperature, low pressure
(iii) Low temperature, high pressure
(iv) High temperature, high pressure
(ii) High temperature, low pressure
(iii) Low temperature, high pressure
(iv) High temperature, high pressure
Answer:
(iii) Low temperature, high pressure
3. The property of flow is unique to fluids. Which one of the following statement is correct ?
(i) Only gases behave like fluids
(ii) Gases and solids behave like fluids
(iii) Gases and liquids behave like fluids
(iv) Only liquids are fluids
(ii) Gases and solids behave like fluids
(iii) Gases and liquids behave like fluids
(iv) Only liquids are fluids
Answer:
(iii) Gases and liquids behave like fluids
4. During summer, water kept in an earthen pot becomes cool because of the phenomenon of
(i) Diffusion
(ii) Transpiration
(iii) Osmosis
(iv) Evaporation
(ii) Transpiration
(iii) Osmosis
(iv) Evaporation
Answer:
(iv) Evaporation
5. A few substances are arranged in the increasing order of 'forces of attraction' between their particles. Which one of the following represents a correct arrangement ?
(i) Water, air, wind
(ii) Air, sugar, oil
(iii) Oxygen, water, sugar
(iv) Salt, juice, air
(ii) Air, sugar, oil
(iii) Oxygen, water, sugar
(iv) Salt, juice, air
Answer:
(iii) Oxygen, water, sugar
6. On converting 25℃, 38℃ and 66℃ to Kelvin scale, the correct sequence of temperature will be
(i) 298K, 311K and 339K
(ii) 298K, 300K and 338K
(iii) 273K, 278K and 543K
(iv) 298K, 310K and 338K
(ii) 298K, 300K and 338K
(iii) 273K, 278K and 543K
(iv) 298K, 310K and 338K
Answer:
(i) 298K, 311K and 339K
7. Choose the correct statement from the following :
(i) Conversion of solid into vapour without passing through the liquid state is called vaporisation.
(ii) Conversion of vapour into solid without passing through the liquid state is called sublimation.
(iii) Conversion of vapour into solid without passing through the liquid state is called freezing.
(iv) Conversion of solid into liquid is called sublimation
(ii) Conversion of vapour into solid without passing through the liquid state is called sublimation.
(iii) Conversion of vapour into solid without passing through the liquid state is called freezing.
(iv) Conversion of solid into liquid is called sublimation
Answer:
(ii) Conversion of vapour into solid without passing through the liquid state is called sublimation.
8. The boiling point of diethyl ether, acetone and n-butyl alcohol are 35℃, 56℃ and 118℃ respectively. Which one of the following correctly represents their boiling points in kelvin scale ?
(i) 306K, 329K and 391K
(ii) 308K, 329K and 392K
(iii) 308K, 329K and 391K
(iv) 329K, 392K and 308K
(ii) 308K, 329K and 392K
(iii) 308K, 329K and 391K
(iv) 329K, 392K and 308K
Answer:
(iii) 308K, 329K and 391K
9. Which condition out of the following will increase the evaporation of water ?
(i) Increase in temperature of water
(ii) Decrease in temperature of water
(iii) Less exposed surface area of water
(iv) Adding common salt to water
(ii) Decrease in temperature of water
(iii) Less exposed surface area of water
(iv) Adding common salt to water
Answer:
(i) Increase in temperature of water
10. The boiling point of water at sea level is
(i) 0℃
(ii) 273K
(iii) 373K
(iv) 273℃
(ii) 273K
(iii) 373K
(iv) 273℃
Answer:
(iii) 373K
11. Which of the following has the strongest interparticle forces at room temperature ?
(i) Oxygen
(ii) Water
(iii) Bromine
(iv) Iron
(ii) Water
(iii) Bromine
(iv) Iron
Answer:
(iv) Iron
12. Which of the following condition is most favourable for converting a gas into a liquid ?
(i) High pressure, low temperature
(ii) Low Pressure, low temperature
(iii) Low pressure, high temperature
(iv) High pressure, high temperature
(ii) Low Pressure, low temperature
(iii) Low pressure, high temperature
(iv) High pressure, high temperature
Answer:
(i) High pressure, low temperature
13. Dry ice is
(i) water in solid state
(ii) water in gaseous state
(iii) CO2 in liquid state
(ii) water in gaseous state
(iii) CO2 in liquid state
(iv) CO2 in solid state
Answer:
Answer:
(iv) CO2 in solid state
14. When a crystal of potassium permagnate is placed at the bottom of water in a beaker, the water in the whole beaker turns purple on its own, even without stirring. This is an eample of :
(i) distribution
(ii) intrusion
(iii) diffusion
(iv) effusion
Answer:
(iii) diffusion
15. Which one of the following statement is correct in respect of fluids ?
(i) only gases behave as fluids
(ii) gases and solids behave as fluids
(iii) gases and liquids behave as fluids
(iv) only liquids are fluids
Answer:
(iii) gases and liquids behave as fluids
16. Out of the following, an eample of matter which can be termed as fluid is :
(i) carbon
(ii) sulphur
(iii) oxygen
(iv) phosphorus
Answer:
(iii) oxygen
17. The best evidence for the existence and movement of particles in liquids was provided by :
(i) John Dalton
(ii) Ernest Rutherford
(iii J.J Thomson
(iv) Robert Brown
Answer:
(iv) Robert Brown
18. A form of matter has no fixed shape but it has a fixed volume. An example of this form of matter is :
(i) krypton
(ii) kerosene
(iii) carbon steel
(iv) carbon dioxide
Answer:
(ii) kerosene
19. Which of the following statement is incorrect ?
(i) the particles of matter are very, very small
(ii) the particles of matter attract one another
(iii) the particles of some of the matter are moving constantly
(iv) the particles of all the matter have spaces between them
Answer:
(iii) the particles of some of the matter are moving constantly
20. When a gas jar is full of air is placed upside down on a gas jar full of Bromine vapours, the red - brown vapours of Bromine from the lower jar go upward into the jar containing air. In this eperiment :
(i) air is heavier than bromine
(ii) both air and bromine have the same density
(iii) bromine is heavier than air
(iv) bromine cannot be heavier than air because it is going upwards against gravity
Answer:
(iii) bromine is heavier than air
21. When a gas jar containing colourless air is kept outside down over a gas jar full of Brown - coloured bromine vapour, then after some time, the brown colour of bromine vapour spreads into the upper gas jar making both the gas jars appear brown in colour. Which of the following conclusion obtained from these observations is incorrect ?
(i) bromine vapour is made of tiny particles which are moving
(ii) air is made up of tiny particles which are moving
(iii) the particles of bromine are moving but those of air are not moving
(iv) even though bromine vapour is heavier than air, it can move up against gravity
Answer:
(iii) the particles of bromine are moving but those of air are not moving
22. Which one of the following statements is not true ?
(i) the molecules in a solid vibrate about a fixed position
(ii) the molecules in a liquid are arranged in a regular pattern
(iii) the molecules in a gas exert negligibly small forces on each other, except during collisions
(iv) the molecules of a gas occupy all the space available
Answer:
(ii) the molecules in a liquid are arranged in a regular pattern
23. Evaporation of a liquid occurs at
(i) boiling point
(ii) a fixed temperature
(iii) temperature lower than boiling point
(iv) all temeperatures
Answer:
(iii) temperature lower than boiling point
24. The conversion of gas into liquid is called
(i) freezing
(ii) condensation
(iii) sublimation
(iv) fusion
Answer:
(ii) Condensation
25. The fusion is the process in which
(i) liquid changes into solid
(ii) solid changes into liquid
(iii) solid changes into gas
(iv) gas changes into solid
Answer:
(ii) solid changes into liquid
26. The ice floats on water because
(i) its density is more than water
(ii) its density is less than water
(iii) it has less intermolecular space
(iv) none of the above
Answer:
(ii) its density is less than water
27. The density of water is maximum at
(i) 0℃
(ii) 100℃
(iii) 4℃
(iv) 273K
Answer:
(iii) 4℃
28. Solids and gases mix/dissolve in water
(i) because water is a good solvent
(ii) because water has intermolecular space
(iii) diffusion is faster in water
(iv) all of th above
Answer:
(d) all of the above
29. One of the following does not undergo sublimation. This one is :
(i) iodine
(ii) sodium chloride
(iii) ammonium chloride
(iv) camphor
Answer:
(ii) sodium chloride
30. If the temperature of an object is 268 K, it will be euivalent to :
(i) -5℃
(ii) +5℃
(iii) 368℃
(iv) -25℃
Answer:
(i) -5℃
31. The boiling point of ethane is , -88℃. This temperature will be equivalent to :
(i) 285 K
(ii) 288 K
(iii) 185 K
(iv) 361 K
Answer:
(iii) 185 K
32. When heat is constantly supplied by a gas burner with small flame to melt ice, then the temperature of ice during melting :
(i) increases very slowly
(ii) does not increase at all
(iii) first remains constant and then increases
(iv) increases to form liquid water
Answer:
(ii) does not increase at all
33. When water at 0℃ freezes to form ice at the same temperature of 0℃, then it :
(i) absorbs some heat
(ii) releases some heat
(iii) neither absorbs nor releases heat
(iv) absorbs exactly 3.34 × 105J/kg of heat
Answer:
(ii) releases some heat
34. When heat is constantly supplied by a burner to boiling water, then the temperature of water during vaporisation :
(i) rises very slowly
(ii) rises rapidly until steam is produced
(iii) first rises and then becomes constant
(iv) does not rise at all
Answer:
(iv) does not rise at all
35. The latent heat of fusion of ice is :
(i) 33.4 ×105J/kg
(ii) 22.5 × 105J/kg
(iii) 33.4 × 104J/kg
(iv) 2.25 × 104J/kg
Answer:
(iii) 33.4 × 104J/kg
36. The latent heat of vaporisation of water is :
(i) 2.25 × 106J/kg
(ii) 3.34 × 106J/kg
(iii) 22.5 × 104J/kg
(iv) 33.4 × 105J/kg
Answer:
(i) 2.25 × 106J/kg
37. Which of the following energy is absorbed during the change of state of a substance ?
(i) specific heat
(ii) latent heat
(iii) heat capacity
(iv) heat of solution
Answer:
(ii) latent heat
38. During respiration, glucose and oxygen enter our body cells and waste products carbon dioxide and water leave the body cells by the process of :
(i) effusion
(ii) osmosis
(iii) diffusion
(iv) plasmolysis
Answer:
(iii) diffusion