Q1. Which of the following conditions is most favourable for converting a gas into a liquid?
(a) High pressure, low temperature
(b) Low pressure, low temperature
(c) Low pressure, high temperature
(d) High pressure, high temperature
Answer
Answer: (a) High pressure, low temperature
Q2. Dry ice is
(a) water in solid state
(b) water in gaseous state
(c) CO2 in liquid state
(d) CO2 in solid state
Answer
Answer: (d) CO2 in solid state
Q3. During summer, water kept in an earthen pot becomes cool because of the phenomenon of
(a) diffusion
(b) transpiration
(c) osmosis
(d) evaporation
Answer
Answer: (d) evaporation
Q4. 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?
(a) Water, air, wind
(b) Air, sugar, oil
(c) Oxygen, water, sugar
(d) Salt, juice, air
Answer
Answer: (c) Oxygen, water, sugar
Q5. On converting 25°C, 38°C and 66°C to Kevlin scale, the correct sequence of temperature will be
(a) 298 K, 311 K and 339 K
(b) 298 K, 300 K and 338 K
(c) 273 K, 278 K and 543 K
(d) 298 K, 310 K and 338 K
Answer
Answer: (a) 298 K, 311 K and 339 K
Q6. Choose the correct statement from the following:
(a) Conversion of solid into vapour without passing through the liquid state is called vapourisation.
(b) Conversion of vapour into solid without passing through the liquid state is called sublimation.
(c) Conversion of vapour into solid without passing through the liquid state is called freezing.
(d) Conversion of solid into liquid is called sublimation.
Answer
Answer: (b) Conversion of vapour into solid without passing through the liquid state is called sublimation.
Q7. In which of the following conditions, the distance between the molecules of hydrogen gas would increase?
(i) Increasing pressure on hydrogen contained in a closed container
(ii) Some hydrogen gas leaking out of the container
(iii) Increasing the volume of the container of hydrogen gas
(iv) Adding more hydrogen gas to the container without increasing the volume of the container
(a) (i) and (iii)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) (ii) and (iv)
Answer
Answer: (c) (ii) and (iii)
Q8. The boiling point of water at sea level is
(a) 0°C
(b) 273 K
(c) 373 K
(d) 273°C
Answer
Answer: (c) 373 K
Q9. Which of the following phenomena would increase on raising the temperature?
(a) Diffusion, evaporation, compression of gases
(b) Evaporation, compression of gases, solubility
(c) Evaporation, diffusion, expansion of gases
(d) Evaporation, solubility, diffusion, compression of gases
Answer
Answer: (c) Evaporation, diffusion, expansion of gases
Q10. Seema visited a Natural Gas Compressing unit and found that the gas can be liquefied under specific conditions of temperature and pressure. While sharing her experience with friends she got confused. Help her to identify the correct set of conditions.
(a) Low temperature, low pressure
(b) High temperature, low pressure
(c) Low temperature, high pressure
(d) High temperature, high pressure
Answer
Answer: (c) Low temperature, high pressure