A solid weighs 200 gf in air, 160 gf in water and 170 gf in a liquid. Calculate the relative density of the solid and that of the liquid?

Sure, let's solve this step by step.

Step 1: Calculate the Relative Density of the Solid

The relative density of a substance is the ratio of the weight of a given volume of the substance to the weight of an equal volume of a reference substance (usually water).

In this case, the weight of the solid in air is 200 gf and the weight of the solid in water is 160 gf. The loss of weight in water is therefore 200 gf - 160 gf = 40 gf.

The relative density of the solid (also known as specific gravity) is the weight of the solid in air divided by the loss of weight in water.

So, the relative density of the solid = 200 gf / 40 gf = 5.

Step 2: Calculate the Relative Density of the Liquid

The weight of the solid in the liquid is 170 gf. The loss of weight in the liquid is therefore 200 gf - 170 gf = 30 gf.

The relative density of the liquid is the weight of the solid in air divided by the loss of weight in the liquid.

So, the relative density of the liquid = 200 gf / 30 gf = 6.67 (rounded to two decimal places).

So, the relative density of the solid is 5 and the relative density of the liquid is 6.67.