Given the equation 2Si(s) + 2Cl2(g) --> 2SiCl2(g) + 687 kJ, how much heat is produced when 106 g of Cl2 react?

514 kJ

General Formulas and Concepts:

Atomic Structure

Stoichiometry

Explanation:

Step 1: Define

Identify

[Given] rxn (balanced): 2Si (s) + 2Cl₂ → 2SiCl₂ (g) + 687 kJ

[Given] 106 g Cl₂

[Solve] kJ heat

Step 2: Identify Conversions

[rxn] 2 mol Cl₂ → 687 kJ

[PT] Molar Mass of Cl: 35.45 g/mol

Molar Mass of Cl₂: 2(35.45) = 70.9 g/mol

Step 3: Stoichiometry

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

513.554 kJ ≈ 514 kJ

Topic: AP Chemistry

Unit: Thermochemistry