Question

How many atoms of aluminium are contained in 2.75 mol

Answer 1

Answer:

1.66 × 10²⁴ atoms Al

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
• Moles
• Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Stoichiometry

• Using Dimensional Analysis

Explanation:

Step 1: Define

[Given] 2.75 mol Al

[Solve] atoms Al

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

1. [DA] Set up:                                                                                                     $\displaystyle 2.75 \ mol \ Al(\frac{6.022 \cdot 10^{23} \ atoms \ Al}{1 \ mol \ Al})$
2. [DA] Multiply [Cancel out units]:                                                                       $\displaystyle 1.65605 \cdot 10^{24} \ atoms \ Al$

Step 4: Check

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

1.65605 × 10²⁴ atoms Al ≈ 1.66 × 10²⁴ atoms Al