In order to run an experiment, a student needs 0.05 kg of HCl for an experiment. In his lab he has available 2.0 kg of an 8.0 mass% solution of HCl in water. Find the mass of solution in grams that the student should use.
To find the mass of the HCl solution the student should use, we need to find the mass of the HCl present in the 2.0 kg solution.
The mass percent is calculated as:
mass percent = (mass of solute / mass of solution) * 100%
We are given that the mass percent of the solution is 8.0% and the mass of the solution is 2.0 kg.
Let's use x to represent the mass of the HCl in the solution.
8.0% = (x / 2.0 kg) * 100%
To solve for x, we can rearrange the equation:
x = (8.0% / 100%) * 2.0 kg
x = (0.08) * 2.0 kg
x = 0.16 kg
Therefore, the mass of the HCl in the solution is 0.16 kg or 160 grams.
Since the student needs only 0.05 kg (or 50 grams) of HCl for the experiment, the mass of the solution that the student should use is 160 grams.