Question

2) The density of ethanol is 789 kg/m³. If a type of hand sanitizer is 60% ethanol by mass, how many mL of

ethanol are in a 100 g of this hand sanitizer?

Answer 1

76.04mL

Explanations

The formula for calculating the density of a substance is expressed as:

`Density=(Mass)/(volume)`

60% m/m = 60 g of ethanol in 100 g of solution

Given that the density of ethanol = 789 kg/m³.

Convert the 60%m/m mass to kg to have;

mass of ethanol required = 0.06kg

Determine the volume

`\begin{gathered} volume=(mass)/(density) \\ volume=(0.06)/(789) \\ volume=0.00007604m^3 \end{gathered}`

Convert cubic meters to mL

Since 1m³ = 10⁶mL, hence

0.00007604m³ = 0.00007604 * 10⁶

0.00007604m³ = 76.04mL

Hence the volume of ethanol that are in a 100 g of this hand sanitizer is 76.04mL