#### Answer

Density=1622 kg/$m^{3}$
It does not float on water.

#### Work Step by Step

This question is a density calculation. We are given a mass of 40.55 g and a volume of 25.0 mL. We have to use the density formula, of d=m/v. We have to convert our units first. We have to convert grams to kilograms and mL to $m^{3}$. There are 1000 grams in a kilogram and 1e6 mL in a cubic meter. When you convert the measurements, you find that the substance has a mass of .04055 kg and a volume of 2.5e-5 cubic meters. When we do this calculation, we find that the density is equal to 1622 kg/$m^{3}$. The second part of the problem asks whether the substance floats on water. For it to float, the density need to be less than that of water. Since water has a density of 1000 kg/$m^{3}$. Since 1622>1000, the substance sinks.