```Determine the mass of the stated number of moles.

1.	2.55 mole Cu2CrO4	8.	1.95 mole HNO3		15.	2.00 mole HC2H3O2
2.	10.0 mole NaCl		9.	2.20 mole SnCl2		16.	5.00 mole Ag2O
3.	3.00 mole H2		10.	3.27 mole O2		17.	0.000300 mole AuCl3
4.	1.55 mole KrF2		11.	0.100 mole NH3		18.	0.00550 mole CH4
5.	0.100 mole H2O		12.	0.500 mole CaCO3	19.	0.300 mole H3PO4
6.	1.500 mole K2SO4	13.	0.0010 mole H2SO4	20.	5.0 mole NH4OH
7.	4.50 mole Na2O		14.	0.30 mole HCl		21.	0.00200 mole Na2SO4
```

Here are the solutions. You determine the answers to the proper number of significant figures. Some answers are given.

1. 2.55 mol x 243.0856 g mol¯1 = 619.868 g = 620. g

Notice the use of the decimal after the zero. This is a common way to show three sig. figs. since writing 620 is, by definition, only two s.f.

2. 10.0 mol x 58.3428 g mol¯1

3. 3.00 mol x 2.01594 g mol¯1

4. 1.55 mol x 121.7968 g mol¯1

5. 0.100 mol x 18.01534 g mol¯1

6. 1.500 mol x 174.2542 g mol¯1 = 261.3813 g = 261.4 g

7. 4.50 mol x 61.77894 g mol¯1

8. 1.95 mol x 63.01287 g mol¯1

9. 2.20 mol x 189.596 g mol¯1

10. 3.27 mol x 31.9988 g mol¯1 = 104.636 g = 105 g

11. 0.100 mol x 17.03061 g mol¯1

12. 0.500 mol x 100.08935 g mol¯1

13. 0.0010 mol x 98.07354 g mol¯1

14. 0.30 mol x 36.36097 g mol¯1

15. 2.00 mol x 60.05298 g mol¯1

16. 5.00 mol x 231.7354 g mol¯1

17. 0.00300 mol x 303.3255 g mol¯1 = 0.090998 = 0.0910 g

18. 0.00550 mol x 16.04303 g mol¯1

19. 0.300 mol x 97.99527 g mol¯1

20. 5.0 mol x 35.04595 g mol¯1

21. 0.00200 mol x 141.83714 g mol¯1 = 0.28367 g = 0.284 g