The density bootle used to measure the density of a liquid makes use of the weight of the empty bottle, then the bottle filled with the water and lastly the bottle is weighed with the liquid whose density is to be determined.
Consider that,
The weight of empty bottle = M1g
Weight of bottle when water is filled = M2g
Weight of bottle when the liquid is filled = M3g
The weight of the liquid present in the bottle is:
= (M3−M1)g
Whereas the weight of Water
= (M2−M1)g
We know that, the volume of 1g of pure water = 1cm3
Volume of liquid present in bottle will be same as the volume of water present in the bottle.
= (M2−M1)cm3
∴ Density of Liquid = MassofliquidVolumeofliquid=(M3−M1)g(M2−M1)cm3