Question

Nitrogen dioxide and water react to produce nitric acid, HNO3, and nitrogen oxide.

3NO2 + H2O --> 2HNO3 + NO
How many grams of H2O are needed to produce 45g of NO?
A. 15g
B. 30g
C. 45g
D. 60g

Answer 1

B. 30g. From the balanced chemical equation, we can determine the ratio between moles of water and moles of nitrogen oxide.

Step-by-step explanation:

The correct answer is option B. 30g.

From the balanced chemical equation:

3NO2 + H2O → 2HNO3 + NO

We can see that for every 3 moles of NO2, 1 mole of water is required to produce 1 mole of NO.

Since the molar mass of water (H2O) is 18 g/mol and the molar mass of NO (nitrogen oxide) is 30 g/mol,

we can set up a ratio of moles:

(1 mol H2O / 3 mol NO2) * (18g/mol H2O / 1 mol H2O) * (1 mol NO / 1 mol H2O) * (30g/mol NO / 1 mol NO) = 30g NO

Therefore, to produce 45g of NO, we would need (45g NO / 30g NO) * (3 mol NO2 / 1 mol NO) * (1 mol H2O / 3 mol NO2) * (18g/mol H2O / 1 mol H2O) = 27g H2O.

Using the molar masses of water and nitrogen oxide, we can calculate the mass of water needed to produce a certain mass of nitrogen oxide. In this case, 45g of NO requires 27g of H2O.