1. Mole Calculation Review

2. Objective/Warm-Up  SWBAT perform mole calculations. Explain the picture:

3. Objective/Warm-Up  SWBAT perform mole calculations. Warm-Up:  What is molar mass?  What is Avogadro’s number?

4.  Calculate the number of atoms in 54.0 g of aluminum.  Ans: 1.20 x 10 24 atoms

5. 3.000 moles Na = ______ grams Ans: 68.97 grams

6. 5.00 moles Na = ________ grams Na Ans: 115 grams

7. 810. g Cl = _______ moles Cl Ans: 22.8 moles

8. 3.27 moles of Cl = ____ atoms Cl Ans: 1.97 x 10 24 atoms

9.  Rubidium has two common isotopes, 85 Rb and 87 Rb. If the abundance of 85 Rb is 72.2% and the abundance of 87 Rb is 27.8%, what is the average atomic mass of rubidium?  85.56 amu

10. 7.7 x 10 25 atoms Ni = ____ g Ni Ans: 7.5 x 10 3 grams

11. 56 g N = _______ moles N Ans: 4.0 moles

12. 1.7 moles Ca = _____ grams Ans: 68 grams

13.  Uranium has three common isotopes. If the abundance of 234 U is 0.01%, the abundance of 235 U is 0.71%, and the abundance of 238 U is 99.28%, what is the average atomic mass of uranium?  237.98 amu

14. 0.033 moles Ne = _______ atoms Ans: 2.0 x 10 22 atoms

15. 9.37 x 10 26 atoms Ag = __ moles Ans: 1.56 x 10 3 moles (or 1560 moles)

16. 6.00 moles of Al = ______ atoms Ans: 3.61 x 10 24 atoms

17.  Titanium has five common isotopes: 46 Ti (8.0%), 47 Ti (7.8%), 48 Ti (73.4%), 49 Ti (5.5%), 50 Ti (5.3%). What is the average atomic mass of titanium?  47.92 amu

18. 120. grams O = ___ atoms Ans: 4.52 x 10 24 atoms

19. 51 grams Zn = ______ moles Ans: 0.79 moles

20. 1.2 x 10 24 atoms C = ___ moles Ans: 2.0 moles

21.  63 Cu has an atomic mass of 62.9298 amu and an abundance of 69.09%. The other isotope, 65 Cu, has an abundance of 30.91%. The average atomic mass between these two isotopes is 63.546 amu. Calculate the atomic mass of 65 Cu.  65 Cu = 64.9278 amu

22. 6.0 moles H = _____ grams Ans: 6.0 grams

23.  57.9 grams Ne = _________ atoms  Ans:  1.73 x 10 24 atoms

24.  24 Mg (78.70%), 25 Mg (10.13%), and 26 Mg (11.7%). The average atomic mass of the three isotopes is 24.3050 amu. If the atomic mass of 25 Mg is 24.98584 amu, and 26 Mg is 25.98259 amu, calculate the actual atomic mass of 24 Mg.  24 Mg = 23.80 amu

25.  8.56 x 10 21 atoms = ______ g S  Ans:  0.456 g S