Question

Explain the procedure to determine the density of an unknown liquid using a relative density bottle.

Answer 1

The density of an unknown liquid can be determined using a relative density bottle as follows.

Step 1:Wash the RD bottle with distilled water. Dry it well.

Step 2 ·: Insert the stopper and find its mass using the balance. Note down the mass of the empty RD bottle.

Step 3 : Fill the bottle with distilled water. Insert the stopper. Some water will drain out through the stopper.Dry the bottle well from outside.

Step 4 :Find the mass of the bottle filled with distilled water.

Step 5 :Empty the bottle and dry it well. Fill it with the liquid whose relative density is to be determined and insert the stopper. Some liquid will drain out through the stopper. Dry the bottle well from the outside. Find the mass of the bottle filled with liquid.

Step 6 :Do the calculations as follows. Mass of the empty bottle = m₁

Mass of bottle + distilled water = m₂

mass of bottle + liquid = m₃

mass of distilled water = (m₂- m₁)

relative density of the liquid = $\frac{m_3-m_1}{m_2-m_1}$

mass of liquid = ( m₃- m₁)

as volume of both the liquid and water is same,

density = $\frac{m_3-m_1}{m_2-m_1}\times 1g/c{m}^3$