Question

Arun has prepared 0.01 % (by mass) solution of sodium chloride in water.
Which of the following correctly represents the composition of the solutions?

• A. 1.00 g of NaCl + 100g of water
• B. 0.11g of NaCl + 100g of water
• C. 0.0l g of NaCl + 99.99g of water
• D. 0.10 g of NaCl + 99.90g of water

Answer 1

The correct option is C 0.0l g of NaCl + 99.99g of water

Mass by mass % $=\frac{Massofsolute}{Massofsolution}\times 100$

$=\frac{.01}{100}=0.01$%
$=\frac{.01}{0.01+99.99}\times 100$
$=\frac{0.01}{100}\times 100$
Hence, mass of solute $=0.01$ g and mass of solvent $=99.99gms$.