Question

Calculate the number of moles of nitrogen dioxide, that contain 4.0*1023 nitrogen dioxide molecule.

Answer 1

Answer:

0.66 mol NO₂

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

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

Stoichiometry

• Using Dimensional Analysis

Explanation:

Step 1: Define

4.0 × 10²³ molecules NO₂ (Nitrogen dioxide)

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

1. Set up:                                $\displaystyle 4.0 \cdot 10^{23} \ molecules \ NO_2(\frac{1 \ mol \ NO_2}{6.022 \cdot 10^{23} \ molecules \ NO_2})$
2. Multiply/Divide:                                                                                                   $\displaystyle 0.664321 \ mol \ NO_2$

Step 4: Check

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

0.664321 mol NO₂ ≈ 0.66 mol NO₂