Answer:
1.50 × 10²⁴ atoms C
Explanation:
Step 1: Define
Molar mass of C - 12.01 g/mol
Avagadro's Number: 6.02 × 10²³ atoms, molecules, formula units, etc.
Step 2: Use Dimensional Analysis
= 1.50375 × 10²⁴ atoms C
Step 3: Simplify
We are given 3 sig figs.
1.50375 × 10²⁴ atoms C ≈ 1.50 × 10²⁴ atoms C
Oxygen is the only element in that list, the rest are compounds.
All of the above are correct answers
Answer:
C₆H₈O₆
Explanation:
First off, the<u> percent of oxygen by mass</u> of vitamin C is:
- 100 - (40.9+4.58) = 54.52 %
<em>Assume we have one mol of vitamin C</em>. Then we would have <em>180 grams</em>, of which:
- 180 * 40.9/100 = 73.62 grams are of Carbon
- 180 * 4.58/100 = 8.224 grams are of Hydrogen
- 180 * 54.52/100 = 98.136 grams are of Oxygen
Now we <u>convert each of those masses to moles</u>, using the <em>elements' respective atomic mass</em>:
- C ⇒ 73.62 g ÷ 12 g/mol = 6.135 mol C ≅ 6 mol C
- H ⇒ 8.224 g ÷ 1 g/mol = 8.224 mol H ≅ 8 mol H
- O ⇒ 98.136 g ÷ 16 g/mol = 6.134 mol O ≅ 6 mol O
So the molecular formula for vitamin C is C₆H₈O₆
