Moles I – Introduction

Youtube Video Moles I

Question 1

4. How many atoms are present in 4.55 mol of Fe? 2.74*10^²⁴
5. How many atoms are present in 0.0665 mol of K? 4.00 * 10^²²
6. How many molecules are present in 2.509 mol of H₂S? 1.51 * 10^²⁴
7. How many molecules are present in 0.336 mol of acetylene (C₂H₂)? 2.02 * 10²³
8. How many moles are present in 3.55 × 10^24 Pb atoms? 5.895 moles
9. How many moles are present in 2.09 × 10^22 Ti atoms? 0.0347 moles
10. How many moles are present in 1.00 × 10^23 PF₃molecules? 0.166 moles
11. How many moles are present in 5.52 × 10^25 penicillin molecules? 91.66 moles

Question 2

Determine the molar mass of each substance.

1. Si – 28
2. SiH₄ – 32
3. K₂O – 94
4. Cl₂ – 71
5. SeCl₂ – 150
6. Ca(C₂H₃O₂)₂ – 158

 

Question 3

What is the mass of 4.44 mol of Rb? – 379.62g

What is the mass of 0.311 mol of Xe? – 40.7g

What is the mass of 12.34 mol of Fe₂(SO₄)₃? – 4936g

What is the mass of 0.0656 mol of PbCl₂? – 18.24g

 

Question 4

How many moles are present in 45.6 g of CO? – 1.63 moles

How many moles are present in 0.00339 g of LiF? – 0.000130 moles

How many moles are present in 1.223 g of SF₆? – 0.008374 moles

How many moles are present in 48.8 g of BaCO₃? – 0.248 moles

 

Question 5 

How many moles are present in 54.8 mL of mercury if the density of mercury is 13.6 g/mL? – 3.72 moles

How many moles are present in 56.83 mL of O₂ if the density of O₂ is 0.00133 g/mL? – 0.00236 moles