1. Entry Task: Feb 11th Monday
Write the question down:
Find the empirical formula of a compound containing: 37.5 % C, 12.6 % H, and 49.9% oxygen.
You have ~10 minutes!

2. Agenda: Go over Empirical Formula ws #2 HW: Empirical Formula pre-lab questions

4. Empirical Formula ------------- = 3.04 Moles of Hydrogen ---------
Find the empirical formula of a compound containing: 3.06 % Hydrogen, % Phosphorus, and % Oxygen.
1 mole of H
3.06 g of Hydrogen
= 3.04 Moles of Hydrogen
g of H
1 mole of P
31.63 g of Phosphorus
= 1.02 Moles of Phosphorus
g of P
1 mole of O
65.30 g of Phosphorus
= 4.08 Moles of Oxygen
g of O

5. Empirical Formula H3PO4 = 2.98 Moles of Hydrogen = 4 Moles of Oxygen
Second: Take the smallest mole amount and divided it into all others.
3.04 Moles of Hydrogen
= 2.98 Moles of Hydrogen
1.02 Moles of Phosphorus
4.08 Moles of Oxygen
= 4 Moles of Oxygen
1.02 Moles of Phosphorus
1.02 Moles of Phosphorus
= 1 Moles of Phosphorus
1.02 Moles of Phosphorus
H3PO4

6. Empirical Formula ------------- = 1.22 Moles of Sodium ---------
Find the empirical formula of a compound containing: % Sodium, % Carbon, 3.66 % Hydrogen, and % Oxygen.
1 mole of Na
28.05 g of Sodium
= 1.22 Moles of Sodium
22.9 g of Na
1 mole of C
29.26 g of Carbon
= 2.44 Moles of Carbon
g of C

7. Empirical Formula ------------- = 3.63 Moles of Hydrogen ---------
Find the empirical formula of a compound containing: % Sodium, % Carbon, 3.66 % Hydrogen, and % Oxygen.
1 mole of H
3.66 g of Hydrogen
= 3.63 Moles of Hydrogen
g of H
1 mole of O
39.02 g of Oxygen
= 2.44 Moles of Oxygen
g of O

8. Empirical Formula C2H3O2Na
Take the smallest mole amount and divided it into all others.
2.44 Moles of Carbon
= 2.0 Moles of Carbon
1.22 Moles of Sodium
3.63 Moles of Hydrogen
= 2.97 Moles of Hydrogen
1.22 Moles of Sodium
2.45 Moles of Oxygen
= 2.00 Moles of Oxygen
1.22 Moles of Sodium
1.22 Moles of Sodium
= 1 Moles of Sodium
1.22 Moles of Sodium
C2H3O2Na

9. Empirical Formula ------------- = 0.628 Moles of Potassium ---------
Find the empirical formula of a compound containing: % Potassium, % Manganese, and % Oxygen.
1 mole of K
24.56 g of Potassium
= Moles of Potassium
g of K
1 mole of Mn
34.81 g of Manganese
= Moles Manganese
54.9 g of Mn
1 mole of O
40.50 g of oxygen
= 2.5 Moles of Oxygen
g of O

10. Empirical Formula KMnO4 = 1 Moles of Manganese
Second: Take the smallest mole amount and divided it into all others.
0.634 Moles of Manganese
= 1 Moles of Manganese
0.628 Moles of Potassium
2.5 Moles of Oxygen
= or 4 Moles of Oxygen
0.628 Moles of Potassium
0.628 Moles of Potassium
= 1 Moles of Potassium
0.628 Moles of Potassium
KMnO4

11. Empirical Formula ------------- = 1.64 Moles of Sodium ---------
Find the empirical formula of a compound containing: % Sodium, % Silicon, and % Oxygen.
1 mole of Na
37.70 g of Sodium
= 1.64 Moles of Sodium
22.9 g of Na
1 mole of Si
22.95 g of Silicon
= Moles of Silicon
g of Si
1 mole of O
39.34 g of oxygen
= 2.45 Moles of Oxygen
g of O

12. Empirical Formula Na2SiO3 = 2 Moles of Sodium
Second: Take the smallest mole amount and divided it into all others.
1.64 Moles of Sodium
= 2 Moles of Sodium
0.817 Moles of Silicon
2.45 Moles of Oxygen
= 2.99 or 3 Moles of Oxygen
0.817 Moles of Silicon
0.817 Moles of Silicon
= 1 Moles of Silicon
0.817 Moles of Silicon
Na2SiO3

13. Empirical Formula ------------- = 1.51 Moles of Nitrogen ---------
Find the empirical formula of a compound containing: % Nitrogen, 6.06 % Hydrogen, 24.24% Sulfur, and % Oxygen.
1 mole of N
21.21 g of Nitrogen
= 1.51 Moles of Nitrogen
g of N
1 mole of H
6.06 g of Hydrogen
= 6.01 Moles of Hydrogen
g of H

14. Empirical Formula ------------- = 0.756 Moles of Sulfur ---------
Find the empirical formula of a compound containing: % Nitrogen, 6.06 % Hydrogen, 24.24% Sulfur, and % Oxygen.
1 mole of S
24.24 g of Sulfur
= Moles of Sulfur
g of S
1 mole of O
48.48 g of Oxygen
= 3.03 Moles of Oxygen
g of O

15. Empirical Formula N2H8SO4
Take the smallest mole amount and divided it into all others.
1.51 Moles of Nitrogen
= 2.0 Moles of Nitrogen
0.756 Moles of Sulfur
6.01 Moles of Hydrogen
= 7.95 or 8 Moles of Hydrogen
0.756 Moles of Sulfur
3.03 Moles of Oxygen
= 4 Moles of Oxygen
0.756 Moles of Sulfur
0.756 Moles of Sulfur
= 1 Moles of Sulfur
0.756 Moles of Sulfur
N2H8SO4

16. DO THE PRELAB!!!!