Calculate the mass of sodium (in kg) present in 95 kg of a crude sample of sodium nitrate whose percentage purity is 70%.

Explanation

Sodium Nitrate = `NaNO_(3)`
Molecular mass of Sodium Nitrate = NaNO3 = 23 + 14 + 48
= 85
100% pure 85 g of `NaNO_(3)` contains 23 g of Sodium.
100% pure `95xx10^(3)` g of `NaNO_(3)` will contains` 23/85 xx95 xx 10^(3)`
= `25.70xx10^(3)` g of Sodium.
100% pure NaNO3 contains `25.70xx10^(3)` g of Sodium.
`:. `100% pure `NaNO_(3)` contains `25.70xx10^(3)`g of sodium
`:. `70% pure `NaNO_(3)` will contains `(25.70xx10^(3))/100 xx 70`
17999 (g) or 17.99 kg of Na