chemistry-8

Hydrogen balloons rise in air because, it is

• more denser than air

• less denser than air

Reaction of an element with oxygen makes

• chloride

• oxide

• carbonates

Mercury rises up while temperature increases. This is due to

• expansion of mercury

• contraction of mercury

• container of mercury

A dispersion of two or more substances that have different states of matter

• gel

• colloid

• emulsion

A mixture of two liquids that don’t usually mix, can be mixed with the help of an emulsifier

• gel

• emulsion

All gases at standard temperature and pressure occupy an volume of

• 22.1 litres

• 22.2 litres

• 22.3 litres

• 22.4 litres

Rusting of iron is

• physical change

• chemical change

sublimation of camphor is

• a chemical change

• physical change

Which among these will not affect diffusion

• concentration change

• density change

• same concentration

atmospheric pressure is low on mountain due to

• low air pressure

• high air pressure