Hi guys, here are the answers to the calculation questions on the review. If your numbers are close, but not exact, it's probably because of rounding. If you're way off, let me know. I'll check my math first, but feel free to email (kathleen [dot] mcadam [at] dcdsb [dot] ca/tweet me (@mrsmcadam) a picture of your work and I can let you know if there's a step you missed.
3. a) 399.91 g/mol b) 213.01 g/mol
4. a) 12.36 mol b) 0.030 mol
5. a) 1.32x10^24 molecules b) 6.02x10^22 molecules
6. a) n = 0.039 mol b) n = 0034 mol
7. a) m = 1.21 g b) m = 1041.10 g
8. a) N = 3.05x10^22 atoms Al (don't forget to multiply by 2 as the last step)
b) N = 4.94x10^21 atoms H (don't forget to multiply by 2 as the last step)
12. a) C = 13.65%, F = 86.35% b) Mg = 41.65%, O = 54.86%, H = 3.46%
14. K2Cr2O7 (needed to double all the formulas as you get 3.5 for oxygen)
15. a) Empirical = C3H3O, Molecular = C6H6O2 b) Empirical = NO2, Molecular = N2O4
20. FeO is limiting
20. (the second one, sorry), mass HCl = 6.93 g
21. mass CO2 (theoretical yield) = 382.01 g, percent yield = 67.01%
22. limiting is NH4ClO4, mass AlCl3 (theoretical yield) = 5.33 g, percent yield = 70.17%
THE TEST IS TOMORROW!
*Look at the post below for the breakdown and theory sections to review. Study well, and come tomorrow morning (I'll be in the breakfast club room) or lunch (229 A on 1st, 237 on 2nd & 3rd) for extra help*
3. a) 399.91 g/mol b) 213.01 g/mol
4. a) 12.36 mol b) 0.030 mol
5. a) 1.32x10^24 molecules b) 6.02x10^22 molecules
6. a) n = 0.039 mol b) n = 0034 mol
7. a) m = 1.21 g b) m = 1041.10 g
8. a) N = 3.05x10^22 atoms Al (don't forget to multiply by 2 as the last step)
b) N = 4.94x10^21 atoms H (don't forget to multiply by 2 as the last step)
12. a) C = 13.65%, F = 86.35% b) Mg = 41.65%, O = 54.86%, H = 3.46%
14. K2Cr2O7 (needed to double all the formulas as you get 3.5 for oxygen)
15. a) Empirical = C3H3O, Molecular = C6H6O2 b) Empirical = NO2, Molecular = N2O4
20. FeO is limiting
20. (the second one, sorry), mass HCl = 6.93 g
21. mass CO2 (theoretical yield) = 382.01 g, percent yield = 67.01%
22. limiting is NH4ClO4, mass AlCl3 (theoretical yield) = 5.33 g, percent yield = 70.17%
THE TEST IS TOMORROW!
*Look at the post below for the breakdown and theory sections to review. Study well, and come tomorrow morning (I'll be in the breakfast club room) or lunch (229 A on 1st, 237 on 2nd & 3rd) for extra help*