Question

Ordinary bleach is $5.25$% $NaOCl$ by mass with a density of $1.11g/mL$.
How many grams of $NaOCl$ are in $50mL$ of bleach?

• A. $5.82g$
• B. $2.91g$
• C. $275g$
• D. $11.5g$

Answer 1

The correct option is B $2.91g$

$5.25\%NaOCl$ by mass in ordinary bleach.

Density of Bleach $=\frac{mass}{volume}=1.119g/mL$

Volume of Bleach $=50mL$

So, mass of bleach solution $\left(1.11\right)\times 50=55.5g$ of Bleach

Mass of $NaOCl=5.25\%$ of $\left(55.5g\right)=\frac{5.25}{100}\times 55.5=2.91g$