Question

3. How many grams are in 9.015 x 1035 atoms of Cobalt?​

Answer 1

Answer:

8.822 × 10¹³ g Co

General Formulas and Concepts:

Chemistry - Atomic Structure

• Reading a Periodic Table
• Using Dimensional Analysis
• Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

9.015 × 10³⁵ atoms Co

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Co - 58.93 g/mol

Step 3: Convert

$9.015 \cdot 10^{35} \ atoms \ Co(\frac{1 \ mol \ Co}{6.022 \cdot 10^{23} \ atoms \ Co} )(\frac{58.93 \ g \ Co}{1 \ mol \ Co} )$ = 8.82189 × 10¹³ g Co

Step 4: Check

We are given 4 sig figs. Follow sig fig rules and round.

8.82189 × 10¹³ g Co ≈ 8.822 × 10¹³ g Co