Respuesta :
Answer:
4.98 × 10²³ formula units Ba(NO₃)₂
General Formulas and Concepts:
Math
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
- Left to Right
Chemistry
Atomic Structure
- Reading a Periodic Table
- Moles
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
Stoichiometry
- Using Dimensional Analysis
Explanation:
Step 1: Define
[Given] 216 g Ba(NO₃)₂
[Solve] formula units Ba(NO₃)₂
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of Ba - 137.33 g/mol
[PT] Molar Mass of N - 14.01 g/mol
[PT] Molar Mass of O - 16.00 g/mol
Molar Mass of Ba(NO₃)₂ - 137.33 + 2[14.01 + 3(16.00)] = 261.35 g/mol
Step 3: Convert
- [DA] Set up: [tex]\displaystyle 216 \ g \ Ba(NO_3)_2(\frac{1 \ mol \ Ba(NO_3)_2}{261.35 \ g \ Ba(NO_3)_2})(\frac{6.022 \cdot 10^{23} \ formula \ units \ Ba(NO_3)_2}{1 \ mol \ Ba(NO_3)_2})[/tex]
- [DA] Divide/Multiply [Cancel out units]: [tex]\displaystyle 4.97705 \cdot 10^{23} \ formula \ units \ Ba(NO_3)_2[/tex]
Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
4.97705 × 10²³ formula units Ba(NO₃)₂ ≈ 4.98 × 10²³ formula units Ba(NO₃)₂
Answer:
Explanation:
Given 216g Ba(NO₃)₂ = 216g/261.34g/mol = 0.827mol
0.827mol = 0.827mol x 6.023 x 10²³molecules/mol
= 4.978066886 x 10²³ molecules (calc. ans.)
≅ 4.98 x 10²³ molecules (3 sig. figs. based on given 216g Ba(NO₂)₃)