Question

Calculate the number of grams of 3.24 x 10^22molecules of CH3(CH2)8(OH)2

Answer 1

8.68 g CH₃(CH₂)₈(OH)₂

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

Step-by-step explanation:

Step 1: Define

3.24 × 10²² molecules CH₃(CH₂)₈(OH)₂

Step 2: Identify Conversions

Avogadro's Number

[PT] Molar Mass of C - 12.01 g/mol

[PT] Molar Mass of H - 1.01 g/mol

[PT] Molar Mass of O - 16.00 g/mol

Molar Mass of CH₃(CH₂)₈(OH)₂ - 12.01 + 3(1.01) + 8[12.01 + 2(1.01)] + 2[16.00 + 1.01] = 161.3 g/mol

Step 3: Convert

1. Set up:
   `\displaystyle 3.24 \cdot 10^(22) \ molecules \ CH_3(CH_2)_8(OH)_2((1 \ mol \ CH_3(CH_2)_8(OH)_2)/(6.022 \cdot 10^(23) \ molecules \ CH_3(CH_2)_8(OH)_2)) \cdot ((161.3 \ g \ CH_3(CH_2)_8(OH)_2)/(1 \ mol \ CH_3(CH_2)_8(OH)_2))`
2. Multiply/Divide:
   `\displaystyle 8.67838 \ g \ CH_3(CH_2)_8(OH)_2`

Step 4: Check

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

8.67838 g CH₃(CH₂)₈(OH)₂ ≈ 8.68 g CH₃(CH₂)₈(OH)₂