One of the steps in the commercial process for converting ammonia to nitric acid is the conversion of NH3 to NO: 4 NH31g2 + 5 O21g2¡4 NO1g2 + 6 H2O1g2 In a certain experiment, 2.00 g of NH3 reacts with 2.50 g of O2. (c) How many grams of the excess reactant remain after the limiting reactant is completely consumed?

Verified step by step guidance

1. Step 1: Write down the balanced chemical equation. In this case, it is already provided: 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(g).
2. Step 2: Convert the masses of NH3 and O2 given in the problem to moles. You can do this by dividing the given mass by the molar mass of each compound. The molar mass of NH3 is approximately 17.03 g/mol and the molar mass of O2 is approximately 32.00 g/mol.
3. Step 3: Determine the limiting reactant. This is the reactant that will be completely consumed first in the reaction. You can do this by comparing the mole ratio of the reactants from the balanced chemical equation with the mole ratio of the reactants you have. The reactant with the smaller ratio is the limiting reactant.
4. Step 4: Calculate the amount of the excess reactant that is consumed. You can do this by using the stoichiometry of the reaction from the balanced chemical equation. Multiply the moles of the limiting reactant by the ratio of the moles of the excess reactant to the moles of the limiting reactant from the balanced chemical equation.
5. Step 5: Subtract the amount of the excess reactant that is consumed from the initial amount of the excess reactant. This will give you the amount of the excess reactant that remains after the reaction. Convert this amount from moles back to grams by multiplying by the molar mass of the excess reactant.

Key Concepts

Limiting Reactant

The limiting reactant is the substance that is completely consumed first in a chemical reaction, thus determining the maximum amount of product that can be formed. In this scenario, identifying the limiting reactant is crucial to calculate how much of the other reactant remains after the reaction has occurred.

Stoichiometry

Stoichiometry involves the calculation of reactants and products in chemical reactions based on balanced equations. It allows us to determine the mole ratios of the reactants and products, which is essential for finding out how much of each reactant is used and how much remains after the reaction.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole. To solve the problem, it is necessary to convert the given masses of NH3 and O2 into moles using their respective molar masses, which will facilitate the stoichiometric calculations needed to identify the limiting reactant and the excess remaining.