Question

Calculate the number of particles in 5.0 grams of NaCl.

Answer 1

5.2 × 10²² particles NaCl

General Formulas and Concepts:

Chemistry - Atomic Structure

• Reading a Periodic Table
• Using Dimensional Analysis
• Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Step-by-step explanation:

Step 1: Define

5.0 g NaCl

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Na - 22.99 g/mol

Molar Mass of Cl - 35.45 g/mol

Molar Mass of NaCl - 22.99 + 35.45 = 58.44 g/mol

Step 3: Convert

`5.0 \ g \ NaCl((1 \ mol \ NaCl)/(58.44 \ g \ NaCl) )((6.022 \cdot 10^(23) \ particles \ NaCl)/(1 \ mol \ NaCl) )` = 5.15229 × 10²² particles NaCl

Step 4: Check

We are given 2 sig figs. Follow sig fig rules and round.

5.15229 × 10²² particles NaCl ≈ 5.2 × 10²² particles NaCl