The chemical reaction of hydrogen with oxygen produces water.
2 H₂(g) + O₂(g) → 2 H₂O(g)
c. How many moles of H₂O form when 2.5 moles of O₂ reacts?

Verified step by step guidance

1. Identify the balanced chemical equation: 2H₂(g) + O₂(g) → 2H₂O(g). This equation shows the stoichiometric relationship between the reactants and products.
2. Determine the mole ratio between O₂ and H₂O from the balanced equation. For every 1 mole of O₂, 2 moles of H₂O are produced. This can be written as a ratio: \( \frac{2 \text{ moles of H₂O}}{1 \text{ mole of O₂}} \).
3. Start with the given amount of O₂, which is 2.5 moles. Use the mole ratio to convert moles of O₂ to moles of H₂O.
4. Set up the conversion: \( 2.5 \text{ moles of O₂} \times \frac{2 \text{ moles of H₂O}}{1 \text{ mole of O₂}} \).
5. Perform the multiplication to find the number of moles of H₂O formed. This will give you the final answer in moles of H₂O.

Key Concepts

Stoichiometry

Stoichiometry is the branch of chemistry that deals with the quantitative relationships between the reactants and products in a chemical reaction. It allows us to calculate how much of each substance is involved in the reaction based on the balanced chemical equation. In this case, it helps determine the amount of water produced from a given amount of oxygen.

Mole Ratio

The mole ratio is derived from the coefficients of a balanced chemical equation and indicates the proportion of moles of one substance to another. In the reaction 2H₂ + O₂ → 2H₂O, the mole ratio between O₂ and H₂O is 1:2. This means that for every mole of O₂ consumed, two moles of H₂O are produced, which is essential for calculating the amount of water formed.

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, understanding which reactant limits the formation of water is crucial for accurately calculating the moles of H₂O produced when 2.5 moles of O₂ reacts.