| Question | Answer |
| 1. Why is the mole used in Chemistry? | to count large numbers of small particles
|
2. The mole is the SI unit for _____________. | amount of matter
| 3. What is one mole equal to? | 6.02 x 10^23, 22.4L, grams of a substance
| 4. One mole of Ca and one mole of O have the same ___________ and different ______. | same number of particles and different masses
| 5. What is the mass of one mole of Mg? | 24.3050g
| 6. What is the molar mass of one mole of Mg? | 24.3050g/mol
| 7. What is the average atomic mass of Mg? | 24.3050u
| 8. What is the mass number of Mg? | 24.3050
| 9. What is the molar mass of Al2S3? | 150.155g/mol
| 10.How many moles are there in 60.5g of Br? | 0.757mol Br
| 11.How many grams are there in 3.56mol of K? | 139g K
| 12.How many particles are there in 0.56mol of Fe? | 3.4x10^23
| 13.How many moles are there in 4.03x10^23particles of Al? | 0.669mol Al
| 14.How many liters are there in 0.289mol of N? | 6.47L N
| 15.How many moles are there in 78.4L of O2? | 3.5mol O2
| 16.How many grams are there in 8.03x10^23atoms of Rb? | 114g Rb
| 17.How many particles are there in 456.4g of Si? | 9.783x10^24
| 18.How many liters are there in 1,203.4g of B? | 2,493.4L B
| 19.How many particles are in 93.7liters of N2 gas? | 2.52x10^24
| 20.What is the percent composition of Mg(OH)2? | Mg=41.38%, O=55.17%, H=3.45%
| 21.What is the percent composition of potassium in KCl? | K=52.52%
| 22.What is the formula that has the smallest whole-number ratio of the elements? | empirical formula
| 23.What is the formula that specifies the actual number of atoms of each element in one molecule or formula unit of the substance? | molecular formula
| 24.The molar mass of nicotine is 162.1 g/mol. It contains 74.0% carbon, 8.7% hydrogen and 17.3% nitrogen. Determine nicotine’s empirical formula and molecular formula. | empirical=C5H7N and molecular=C10H14N2
| 25. Phenyl magnesium bromide is used as a Grignard reagent in organic synthesis. Determine its empirical and molecular formula if its molar mass is 181.313 g/mol and it contains 39.7458% C, 2.77956% H, 13.4050% Mg and 44.0697% Br. | empirical and molecular are C6H5MgBr |
