Final answer:
To find the percent by mass of HCl in the tile cleanser with 135 g HCl and 775 g water, you divide the mass of HCl by the total mass then multiply by 100%, yielding about 14.84% HCl.
Step-by-step explanation:
To calculate the percent by mass of HCl in a tile cleanser that contains 135 g of HCl and 775 g of water, you would use the formula for mass percentage. The formula is:
Mass percent of a component = (mass of the component / total mass of the solution) × 100%
Applying the formula:
Mass percent of HCl = (135 g / (135 g + 775 g)) × 100%
Calculating this gives:
Mass percent of HCl = (135 g / 910 g) × 100%
Mass percent of HCl ≈ 14.84%
Therefore, the percent by mass of HCl in the cleanser is approximately 14.84%.