Question

3. How many grams of H2O would be produced if 20.5 grams H2 react with 80.5 grams 02 inthe reaction:H2 +02 →H20

Answer 1

Explanation:

We first start by balancing the given reaction:

$2H_2\text{ + O}_2\text{ }\rightarrow\text{ 2H}_2O$

Then we determine the mass of H2O from H2:

$\begin{gathered} m(H2O)\text{ = }\frac{m(H2)}{M(H2)}\text{ }\times\text{ }\frac{mol(H2O)}{mol(H2)}\text{ }\times\text{ M\lparen H2O\rparen} \\ \\ \text{ = }\frac{20.5}{2.016}\times\frac{2}{2}\text{ }\times18.01528 \\ \\ \text{ = 183.19g} \end{gathered}$

Then we determine the mass of H2O from O2:

$\begin{gathered} m(H2O)\text{ = }\frac{m(O2)}{M(O2)}\text{ }\times\frac{mol(H2O)}{mol(O2)}\text{ }\times\text{ M\lparen H2O\rparen} \\ \\ \text{ = }\frac{80.5}{32}\text{ }\times\frac{2}{1}\text{ }\times\text{ 18.01528} \\ \\ \text{ = 90.64g} \end{gathered}$

Answer:

mass of H2O = 90.64g