An empty relative density bottle has a mass of 30g. When filled with paraffin,its mass is 70g. Calculate the mass of the bottle when it is filled with water.

(relative density of paraffin=0.8)

4 answers

70 -30 = 40g = Wt. of paraffin.
V = 40g/(0.8g/cm^3) = 50cm^3 = Vol. of bottle.

Mass = 30 + (50cm^3*1g/cm^3) = 80g When filled with water.
How can we determine a relative density of an object
I don't know
To determine the relative density of an object, follow these steps:

1. Find the object's mass using a weighing scale.

2. Find the object's volume using a suitable method. This can be done by measuring its dimensions and using an appropriate formula or by submerging it in water and measuring the volume of water displaced.

3. Divide the object's mass by its volume to get its density.

4. Compare the object's density to the density of a reference substance or material, which is typically water for solids and liquids. This will give you the relative density (also called specific gravity) of the object.

Relative Density = Density of Object/Density of Reference Substance

Note that relative density is a dimensionless quantity and has no units.