Question

What is the mass of 6.40 moles of copper(II)chloride (CuCl2)?

Answer 1

860. g CuCl₂

General Formulas and Concepts:

Atomic Structure

• Reading a Periodic Table
• Compounds
• Moles

Stoichiometry

• Using Dimensional Analysis

Step-by-step explanation:

Step 1: Define

[Given] 6.40 mol CuCl₂

[Solve] g CuCl₂

Step 2: Identify Conversions

[PT] Molar Mass of Cu: 63.55 g/mol

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

Molar Mass of CuCl₂: 63.55 + 2(35.45) = 134.45 g/mol

Step 3: Convert

1. [DA] Set up:
   `\displaystyle 6.40 \ mol \ CuCl_2((134.45 \ g \ CuCl_2)/(1 \ mol \ CuCl_2))`
2. [DA] Multiply [Cancel out units]:
   `\displaystyle 860.48 \ g \ CuCl_2`

Step 4: Check

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

860.48 g CuCl₂ ≈ 860. g CuCl₂