Question

A scientist compares two samples of white powder. one powder was present at the beginning of an experiment. the other powder was present at the end. she wants to determine whether a chemical reaction has occurred. she finds that neither sample bubbles or dissolves in water. she measures the mass and volume of the solids. sample one has a volume of 45 cm3 and a mass of 0.5
g. sample two has a volume of 65 cm3 and a mass of 1.3
g. what should the scientist conclude?

Answer 1

Answer. Chemical reaction had occurred and both the powders are different substances.

Explanation:

As density is an intensive property of the substance.Which means that  different substance have different densities.

Density = $\frac{mass}{volume}$

Density of powder 1, $d_1=\frac{0.5g}{45cm^3}=0.11g/cm^3$

Density of powder 2, $d_2=\frac{1.3g}{65cm^3}=0.02g/cm^3$

On comparing both the densities of the powders we can say that both the substances are different. So we can conclude that the chemical reaction had occurred.

Answer 2

I think that the scientist should conclude that there was no chemical reaction. There were no clear evidences that a reaction had occurred. The variation in the volume and the mass was not an indication whether a reaction happened. Hope this answers the question. Have a nice day.