Question

When $Ag{NO}_3$ was treated with 5.08g of a sample iron chloride, 11.48g pf AgCL was formed 6.51g of another iron chloride gave 17.22g of AgCI on treatment with $Ag{NO}_3$. Show that these results illustrate the law of multiplle proportions.

[R.A.M. Ag = 108, Fe = 56 and CI = 35.5]

Answer 1

For 1st case, $xAgN{O}_3+FeC{l}_x\to xAgCl$

1 mol of $FeC{l}_x$ gives x moles of $AgCl$.

$\therefore \frac{5.08}{56+35.5x}mol$ gives $\frac{5.08}{56+35.5x}molesAgCl$

$\therefore \frac{5.08}{56+35.5x}=\frac{11.48}{143.5}$

$\Rightarrow x=2$

For 2nd case, $yAgN{O}_3+FeC{l}_y\to yAgCl$

1 mol of $FeC{l}_y$ gives y moles $AgCl$

$\therefore \frac{6.51}{56+35.5y}mol$ gives $\frac{6.51}{56+35.5y}molesAgCl$

$\therefore \frac{6.51}{56+35.5y}=\frac{17.22}{143.5}=0.12$

$\Rightarrow y\approx 3$

$\Rightarrow \frac{x}{y}=\frac{2}{3}\to$ This is in accordance with law of proportions.