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Please help!!
I don’t understand

Please help!! I don’t understand-example-1

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7 votes

Answer:

150 g Si

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

  • Use Dimensional Analysis

Step-by-step explanation:

Step 1: Define

[Given] 3.2 × 10²⁴ atoms Si

[Solve] grams Si

Step 2: Identify Conversions

Avogadro's Number

[PT] Molar Mass of Si - 28.09 g/mol

Step 3: Convert

  1. [DA] Set up:
    \displaystyle 3.2 \cdot 10^(24) \ atoms \ Si((1 \ mol \ Si)/(6.022 \cdot 10^(23) \ atoms \ Si))((28.09 \ g \ Si)/(1 \ mol \ Si))
  2. [DA] Multiply/Divide [Cancel out units]:
    \displaystyle 149.266 \ g \ Si

Step 4: Check

Follow sig fig rules and round. Instructed to round to 2 sig figs.

149.266 g Si ≈ 150 g Si

User Kristian Evensen
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