Respuesta :

Space

Answer:

1.54 × 10²⁴ atoms He

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

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

Stoichiometry

  • Using Dimensional Analysis

Explanation:

Step 1: Define

[Given] 2.56 moles He

[Solve] atoms He

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

  1. [DA] Set up:                                                                                                      [tex]\displaystyle 2.56 \ mol \ He(\frac{6.022 \cdot 10^{23} \ atoms \ He}{1 \ mol \ He})[/tex]
  2. [DA] Multiply [Cancel out units]:                                                                     [tex]\displaystyle 1.54163 \cdot 10^{24} \ atoms \ He[/tex]

Step 4: Check

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

1.54163 × 10²⁴ atoms He ≈ 1.54 × 10²⁴ atoms He