Question

How many zinc atoms are contained in 3.75 moles of zinc?

Answer 1

Answer:

2.26 × 10²⁴ atoms Zn

General Formulas and Concepts:

Math

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Chemistry

Atomic Structure

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

Stoichiometry

• Using Dimensional Analysis

Explanation:

Step 1: Define

3.75 mol Zn (Zinc)

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

1. [DA] Set up:                                                                                                     $\displaystyle 3.75 \ mol \ Zn(\frac{6.022 \cdot 10^{23} \ atoms \ Zn}{1 \ mol \ Zn})$
2. [DA] Multiply/Divide [Cancel out units]:                                                        $\displaystyle 2.25825 \cdot 10^{24} \ atoms \ Zn$

Step 4: Check

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

2.25825 × 10²⁴ atoms Zn ≈ 2.26 × 10²⁴ atoms Zn