Question

How many moles are in 1.51x10^26 atoms of xenon (Xe)? Please and thank you :)!!

Answer 1

Answer:

251 mol Xe

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

[Given] 1.51 × 10²⁶ atoms Xe

[Solve] moles Xe

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

1. [DA] Set up:                                                                                                     $\displaystyle 1.51 \cdot 10^{26} \ atoms \ Xe(\frac{1 \ mol \ Xe}{6.022 \cdot 10^{23} \ atoms \ Xe})$
2. [DA] Multiply/Divide [Cancel out units]:                                                         $\displaystyle 250.747 \ mol \ Xe$

Step 4: Check

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

250.747 mol Xe ≈ 251 mol Xe