Question

when the sample burns, 0.1159 g h₂o also form. how many moles of hydrogen are in the sample? ? mol h this is not a final result. record at least six digits!

Explanation:

Step1: Calculate moles of \(H_2O\)

Molar mass of \(H_2O\) is \(2\times1.008 + 16.00 = 18.016\) g/mol. Moles of \(H_2O=\frac{0.1159\ g}{18.016\ g/mol}\).
\(n(H_2O)=\frac{0.1159}{18.016}\approx0.006433\) mol.

Step2: Relate moles of \(H_2O\) to moles of H

Each \(H_2O\) has 2 H atoms. So moles of H = \(2\times\) moles of \(H_2O\).
\(n(H)=2\times0.006433 = 0.012866\) mol (calculated more precisely: \(2\times\frac{0.1159}{18.016}=\frac{0.2318}{18.016}\approx0.012866\) mol).

Answer:

\(0.012866\) (or more precise value from \(\frac{0.1159\times2}{18.016}\approx0.012866\))