Question

an unknown compound has the following chemical formula:
p_x cl_3
where x stands for a whole number.
measurements also show that a certain sample of the unknown compound contains 6.1 mol of phosphorus and 17.77 mol of chlorine.
write the complete chemical formula for the unknown compound.

Explanation:

Step1: Find the ratio of moles of P to Cl

The ratio of moles of \(P\) to \(Cl\) is \(\frac{n(P)}{n(Cl)}=\frac{6.1}{17.77}\).

Step2: Simplify the ratio

\(\frac{6.1}{17.77}=\frac{6.1\div6.1}{17.77\div6.1}=\frac{1}{2.913}\approx\frac{1}{3}\)

Since the formula is \(P_xCl_3\), and the ratio of \(P:Cl = 1:3\) (from the mole - ratio calculation), \(x = 1\)

Answer:

\(PCl_3\)