# A. The typical concentration for the hydrochloric acid is 18.0% by mass of the solution in water....

## Question:

A. The typical concentration for the hydrochloric acid is 18.0% by mass of the solution in water. The density of this solution is 1.154 grams per millilitre (at 20 degree Celsius) and {eq}6.0 \times 10^5 {/eq} liters of the solution is used per year. How many kilograms of pure hydrochloric acid (not the solution) is used per year? Show your work.

B. The hydrochloric acid density drops 0.010 grams per millilitre for every 1 degree Celsius of temperature drop. If the acid is cooled by 28 degree Fahrenheit, what will be the new density if it started at the same temperature as the problem above? Show your work.

## Density, Volume, and Temperature:

Density is a physical property that describes the distribution of mass in volume. Given that volume changes with temperature, density also changes with temperature. Considering that temperature and volume are directly proportional, the relationship between temperature and density is inversely proportional. When the temperature increases, the density decreases.