Question

Nitric oxide is made from the oxidation of ammonia. What mass of nitric oxide can be made from the reaction of 8.00 g NH 3 with 17.0 g O 2? 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(g)

Answer 1

Answer: The mass of nitric oxide is 12.72 grams

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$     .....(1)

• For ammonia:

Given mass of ammonia = 8.00 g

Molar mass of ammonia = 17 g/mol

Putting values in equation 1, we get:

$\text{Moles of ammonia}=\frac{8.00g}{17g/mol}=0.47mol$

• For oxygen gas:

Given mass of oxygen gas = 17.0 g

Molar mass of oxygen gas = 32 g/mol

Putting values in equation 1, we get:

$\text{Moles of oxygen gas}=\frac{17g}{32g/mol}=0.53mol$

The given chemical reaction follows:

$4NH_3(g)+5O_2(g)\rightarrow 4NO(g)+6H_2O(g)$

By Stoichiometry of the reaction:

5 moles of oxygen gas reacts with 4 moles of ammonia

So, 0.53 moles of oxygen gas will react with = $\frac{4}{5}\times 0.53=0.424mol$ of ammonia

As, given amount of ammonia is more than the required amount. So, it is considered as an excess reagent.

Thus, oxygen gas is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

5 moles of oxygen gas produces 4 moles of NO

So, 0.53 moles of oxygen gas will produce = $\frac{4}{5}\times 0.53=0.424moles$ of NO

Now, calculating the mass of NO from equation 1, we get:

Molar mass of NO = 30 g/mol

Moles of NO = 0.424 moles

Putting values in equation 1, we get:

$0.424mol=\frac{\text{Mass of NO}}{30g/mol}\\\\\text{Mass of NO}=(0.424mol\times 30g/mol)=12.72g$

Hence, the mass of nitric oxide is 12.72 grams