Ch. 11 Mole calculations, etc.

Molar Mass, Volume, Particles, and Mole Calculations

Find the molar mass (g/mole) for each of the compounds below:

1. H3PO4 4. BH3 7. HNO3 10. oxygen

2. CCl4 5. P4O6 8. CO2 11. methane

3. NaOH 6. CF4 9. CO 12. ammonia

Express each of the following in grams:

13. 1.0 mol of CaCl2 16. 1.75 mol of H2O2 19. 0.28 mol of bromine

14. 2.0 mol of AlF3 17. 1.00 mol of KBr 20. 4.8 mol of water

15. 0.30 mol of NaHCO3 18. 3.24 mol of NaCl 21. 2.9 mol of CS2

Convert each of the following to its equivalent in moles.

22. 86.84 g of LiBr 24. 17.1 g of H2S 26. 0.2000 g of cadmium bromide

23. 62.3 g of MgF2 25. 302.7 g of ScCl3 27. 2,378 g of methane

Convert each of the following to its equivalent in moles.

28. 6.02 X 1023 atoms of Mg 30. 4.0 X 1012 f.u. of NaCl 32. 7.89 X 1025 atoms of Sr

29. 2.7 X 1027 molecules of water 31. 1.9 X 1017 f.u. of NaOH 33. 4.3 X 1012 molecules of H2O2

Convert each of the following to its number of particles.

34. 12 mol of NF3 36. 0.70 mol of water 38. 7.12 mol of I2

35. 3.98 mol of BaCl2 37. 1.0 mol of HNO2 39. 6.0 mol of AgNO3

Convert each of the following into liters @ STP.

40. 3.5 mol of C4H10 ­ 42. 1.0 mol of CH3OH ­ 44. 2.6 mol of nitrogen­

41. 0.9 mol of C3H8 ­ 43. 2.9 mol of C6H6 ­ 45. 0.3 mol of hydrogen­

Convert each of the following into moles @ STP.

46. 12.0 L of O2↑ 48. 76.3 L of CO↑ 50. 3.9 L of HCl↑

47. 0.009 L of SO2 49. 4.00 L of CO2↑ 51. 0.2 L of N2↑

Find the percent composition of each of the following compounds.

52. NaCl 54. SO2 56. K2S 58. CaCl2•2H2O

53. HBr 55. H2Te 57. AlI3 59. FePO4•4H2O

60. What is the percent water in BaCl22H2O ?

61. What is the percent water in CuCl25H2O?

Problems

62. Which has more atoms, 10.0 g of C or 10.0 g of Ca?

63. How many molecules of water are there in 15.1g of water?

64. How many liters of SO2(g) are there in 45.0g of SO2?

65. Determine the number of oxygen atoms present in 25.0 g of CO2.

66. How many grams of silver can be recovered from 10.0 lbs. of Ag2S? (454g = 1 lb)

67. How many L of gas at STP are there in 3.45g of N2 gas?

68. How many grams of oxygen gas are there in 73.9 L of oxygen gas at STP?

69. Determine the empirical formula for each of the following compounds.

a. ethylene C2H4 b. ascorbic acid C6H8O6 c. naphthalene C10H8

70. Acetylene gas has a molar mass of 26.04 g and a percent composition of 7.76% hydrogen and 92.24 % carbon.

What is its molecular formula ?