Matter in Our Surroundings

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

• (i) and (iii)

• (i) and (ii)

• (i) and (iv)

• (ii) and (iii)

Plasma was first systematically studied by

Four students took separately the mixture of sand, common salt and ammonium chloride in beakers, added water, stirred the mixture well and then filtered. They reported their observations as shown above.Who reported the observations in the correct order of the components as residue and in the filtrate?

• I

• IV

• III

• II

On converting 308 K, 329 K and 391 K to Celsius scale, the correct sequence of temperatures will be:

• 33°C, 56°C and 118°C

• 35°C, 56°C and 119°C

• 35°C, 56°C and 118°C

• 56°, 119°C and 35° C

Which of the following phenomena always results in the cooling effect?

Condensation, Evaporation, Sublimation

On which year the first gaseous condensate was produced

When a gas jar 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 experiment:

• Air is heavier than bromine

• Both air and bromine have the same density

• Bromine is heavier than air

• Bromine cannot be heavier than air because it is going upwards against gravity

In A Quiz Competition, You Are Asked A Question Where You Have To Choose The Statement Which Is/ Are correct?

• Ammonia gas can be liquefied by applying high pressure and lowering the temperature.

• Solid carbon dioxide is stored under less-high pressure.

• The conversion of solid carbon dioxide into carbon dioxide gas is a change of state which is caused by the increase in pressure and decrease atmospheric temperature.

• Whatever be the temperature at which evaporation take place, the latent heat of vaporization need not be supplied whenever a liquid change into vapour or gas.

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.

• Low temperature, low pressure

• High temperature, low pressure

• Low temperature, high pressure

• High temperature, high pressure

CO2 can be easily liquified and even solidified because

• It has weak forces of attraction

• It has comparatively more force of attraction than other gases

• It has more intermolecular space

• It is present in atmosphere