Question

2. How many moles of Hydrogen gas are needed to produce 4 moles of water?

2 H2(g) + 1 O2(g) → 2 H2O(l)

Answer 1

4 mol H₂

General Formulas and Concepts:

Atomic Structure

• Reading a Periodic Table
• Moles

Aqueous Solutions

• States of matter

Stoichiometry

• Using Dimensional Analysis
• Analyzing reactions RxN

Step-by-step explanation:

Step 1: Define

[RxN - Balanced] 2H₂ (g) + O₂ (g) → 2H₂O (l)

[Given] 4 mol H₂O

[Given] mol H₂

Step 2: Identify Conversions

[RxN] 2 mol H₂ (g) → 2 mol H₂O (l)

Step 3: Stoichiometry

1. [DA] Set up conversion:
   `\displaystyle 4 \ mol \ H_2O((2 \ mol \ H_2)/(2 \ mol \ H_2O))`
2. [DA] Multiply [Cancel out units]:
   `\displaystyle 4 \ mol \ H_2`