1. Avogadro’s Number 6.02 X 10 23

2. 1 Mole 6.02 X 10 23

3. 0.5 Mole 3.01 X 10 23

4. 0.25 Mole 1.50 X 10 23

5. 2.0 Mole 12.04 X 10 23 Or 1.204 X 10 24

6. 1.0 Mole of any gas at STP 22.4 Liters

7. STP Standard Temperature = 0  C Standard Pressure = 1 atm

8. 0.5 mole of any gas 11.2 Liters

9. 2.0 mole of any gas 44.8 Liters

10. 3.0 mole of any gas 67.2 Liters

11. 0.25 mole of any gas 5.6 Liters

12. Gram Atomic Mass Mass of 1 mole of an element.

13. Formula Mass Sum of the masses of the elements in the compound

14. Formula Mass of H 2 O 2 X H = 2 X 1.0 = 2.0 1 X O = 1 X 16.0 = 16.0 Sum = 18.0

15. Formula Mass of NH 3 3 X H = 3 X 1.0 = 3.0 1 X N = 1 X 14.0 = 14.0 Sum = 17.0

16. Formula Mass of CO 2 1 X C = 1 X 12.0 = 12.0 2 X O = 2 X 16.0 = 32.0 Sum = 44.0

17. Count up the atoms in (NH 4 ) 2 SO 4 For Paren: Sub Inside X Sub outside N: 2S: 1 H: 8O: 4

18. Count up the atoms in 2Mg 3 (PO 4 ) 2 For Paren: Sub Inside X Sub outside Coefficients X subs in formula Mg: 6P: 4O: 16

19. # of Moles # of Grams # of Particles # of Liters (gas) X 6.02 X 10 23 X Formula Mass X 22.4 L/mole  by 6.02 X 10 23  by formula mass  by 22.4

20. Percent Part X 100% Whole

21. Percent H in H 2 O Part X 100% = 2 X 100% Whole 18

22. Percent O in H 2 O Part X 100% = 16 X 100% Whole 18

23. Empirical Formula smallest whole number ratio of the elements in a compound

24. Molecular Formula Gives exact composition of molecule

25. Covalent Compound Formula contains all nonmetals

26. Ionic Compound Formula contains metal plus nonmetal

27. CuSO 45H 2 O Formula of a hydrated salt. means “is associated with.” H 2 O molecules are stuffed in the empty spaces.

28. Formula mass of CuSO 45H 2 O Mass of CuSO 4 plus mass of 5 water molecules. 249.6 grams/mole

29. Percent H 2 O in CuSO 4 5H 2 O Part X 100% = 90 X 100% Whole249.6

30. Metals All elements to the left of the staircase except H

31. Nonmetals All elements to the right of the staircase plus H

32. Binary Compound Compound made from 2 elements

33. Which formulas are empirical? H 2 OH 2 O 2 CH 4 C 2 H 6 C 6 H 12 O 6 KClP 4 O 10 CaF 2

34. Given empirical formula & Formula Mass, find Molecular Formula 1)Find empirical mass 2)Divide formula mass/empirical mass 3)Multiply subscripts in empirical formula by answer in step 2

35. Empirical formula = CH & Formula Mass = 78, find Molecular Formula 1)Empirical mass = 13 2)Divide formula mass/empirical mass = 78/13 = 6 3)Multiply subscripts: C 6 H 6

36. 12 grams of hydrated salt is heated. After heating the mass is 8.0 grams. What is the percent salt & the percent H 2 O? 1)Mass of H 2 O = 12 – 8 = 4 g 2)Percent H 2 O = 4/12 X 100% 3)Percent salt = 8/12 X 100%

37. He 1 atom of He or 1 mole of He 1 atom per molecule

38. O2O2 1 molecule of O 2 or 1 mole of O 2 2 atoms per molecule

39. O3O3 1 molecule of O 3 or 1 mole of O 3 3 atoms per molecule