Question

Find percentage mass of water in washing soda crystals

Answer 1

Q. Find percentage mass of water in washing soda crystals.

$\huge{\underline{\tt{\green{Answer-}}}}$

• The percentage mass of water in washing soda crystals is 62.9%.

• Washing soda crystals contain water of crystallization. The chemical formulas of Na₂CO₃.10H₂O.

R.M.M of Na2CO3.10H2O = (23×2) + 12 + (16×3) + 10(2+16) = 106 + 180 = 286 atomic mass unit.

• Now, 286 g of washing soda contains 180 g of water of crystallization

So, 100 g of washing soda contains

$\longrightarrow \tt \frac{ 180\times100}{286 g}$

$\longrightarrow \tt {62.9 g\:of\:H2O}$

• Hence, %mass of H2O in washing soda crystals (Na2CO3.10H2O) = 62.9

$\longrightarrow\huge{\underline{\tt{\green{62.9\%}}}}$

Hence, the percentage mass.

Answer 2

Answer:

62.9 percent............