The mass of an empty density bottle is 21.8 g, when filled completely with water it is 41.8 g and when filled completely with liquid it is 40.6 g. Find:

(a) the volume of density bottle.

(b) the relative density of liquid.

Mass of empty density bottle (M₁) = 21.8 g

Mass of bottle with water (M₂) = 41.8 g

Mass of bottle with liquid (M₃)= 40.6 g

(a) Mass of water in bottle = M₂ - M₁ = 41.8 - 21.8 = 20 g

Density of water is 1 g cm^-3, so volume of density bottle = 20 mL

(b) Mass of liquid in bottle = M₃ - M₁ = 40.6 - 21.8 = 18.8 g

$\text{R.D. of liquid}= \dfrac{\text{Mass of Liquid}}{\text{Mass of eq. vol. of water}} \\[1em] = \dfrac{\text{18.8}}{\text{20}} = 0.94$

Relative density of liquid = 0.94.