The mass per unit volume of a substance is called density. Arrange the following in order of increasing density:air, exh

Solution

The order of increasing density is :

air < exhaust from chimneys < water < honey < cotton < chalk < iron.

Explanation:

air, exhaust from chimney   →  gases

water, honey → liquids

cotton, chalk & Iron → solids

? Among air and exhaust from chimneys, the mass of exhaust from chimneys (which contains some heavier gases like CO2, SO2, NO2 etc and minute solid particles) is much higher than air (which contains only O2 & N2 as main constituents). Therefore, density of exhaust from chimneys is expected to be higher than that of air. Thus, order of densities among different gases like air & exhaust from chimneys is - air < exhaust from chimneys.

? Among honey and water, the mass of particles of honey is much higher and inter particle distances are much smaller than those in water. Therefore, the density of honey is higher than that of water. Thus, order of densities among different liquids like water and honey is - water < honey.

? Among chalk and iron, the mass of the particles of iron is much higher and inter particle distances are much smaller than those in chalk (since particles of iron are very closely packed than of chalk) Therefore, density of iron is much higher than that of chalk. Cotton is also a solid, but its density is lower than that of other solids like chalk & iron due to spaces in which air is trapped. Thus order of densities among different solids like cotton, chalk & iron, is - cotton < chalk < iron.

Order of densities among solids, liquids & gases:

Now since gases have larger inter particle distances than liquids, they have lower densities than liquids.

i.e. air < exhaust from chimneys < water < honey. But since liquids have larger inter particle distances than solids, they have lower densities than solids.

i,e water < honey < cotton < chalk < iron thus the overall order of increasing density is: air < exhaust from chimneys < water < honey < cotton < chalk < iron.