1. Homework 5 due today Wednesday 21 Feb
Exam 1 Friday 23 Feb

2. What to expect on Exam 1:
Prefixes and conversions between them
Sig fig counting and computing
Atomic parts and dimensions
Average atomic masses
Naming compounds
Names/symbols of common elements (Know first 4 rows)
Moles level 1,2
Hint for studying: See homework 1-5 and quiz 1 (answers at website)

3. 1) Convert any mass or count to moles (divide up)
Moles Level 2: `Body Parts’ Calculations the Process
1) Convert any mass or count to moles (divide up)
2) Set up appropriate ratio with unknown mol
quantity (m) and solve for m.
3) If necessary re-convert m to mass or count
(multiply down)

4. how many moles of C6H12O6 can be made with 192 g of O ?
Mole Body Part Calculations level 2: More practice, practice, practice
1)mole to mole:
how many moles of O are present in mole of C6 H12O6?
1 mol O
2)weight to mole
how many moles of C6H12O6 can be made with 192 g of O ?
2 moles C6H12O6

5. 3) weight to moles how many moles of C6H12O6 in a sample containing 216 g C ? (at. wt of C=12 g/mol18
0.333 3 6

6. Mole Calculations: part 2 (cont.)
4) moles to weight (MW
how many grams of C6H12O6 (MW=180 g/mol) are formed with mol H?
= 4 g

7. 5) moles weight How many grams of C6H12O6 (MW=180 g/mol) contain 0
5) moles weight How many grams of C6H12O6 (MW=180 g/mol) contain mol C ?
1.00 g
0.05 g
0.4 g g

8. Mole Calculations: part 2 (cont.)
6) moles to atom count
how many atoms of O are present in mol of C6 H12O6?
=5*1023

9. 7) Moles to atom count: how many atoms of C are in 0
7) Moles to atom count: how many atoms of C are in mol of C6H12O6? (1 mol =6*1023)
1.662*1022
1.3*1024
1.0*1023
1.0*1024

10. 84 *1023 atoms of O 8 grams H 8) mass to molecules:
Mole Calculations: part 2 (cont.)
8) mass to molecules:
how many atoms of H in C6 H12O6 are combined with 84 g of C ?
84 *1023 atoms of O
8) atoms to mass:
how many grams of H are combined with 2.4*1024 atoms of O in C6H12O 6 ?
8 grams H

11. 9) mass molecules: How many molecules of C6H12O6 are present in a sample containing 32 g of O (at. wt=16 g/mol)? 1 1 mol count=6*1023
12*1023
5*1024
3.3*1023
2.0*1023

12. Mole Calculations: part 2 (cont.)
10) atoms to mass:
how many grams of H are combined with 2.4*1024 atoms of O in C6H12O 6 ?
8 grams H

13. Prefixes and conversions between them Sig fig counting and computing
Board examples of exam 1 problems for….
Prefixes and conversions between them
Sig fig counting and computing
Atomic parts and dimensions
Average atomic masses
Naming compounds
Names/symbols of common elements (Know first 4 rows)
Moles level 1,2