Avogadro's number calculations

1. How many atoms are in 0.600 moles of Helium?

9.97 x10^-25

3.61 x10²³

7.22 x10²³

1.00 x10²⁴

Correct! Wrong!

2. How many atoms are in 0.200 moles of Cl₂?

3.01 x10²⁴

1.51 x10²⁴

1.20 x10²³

2.41 x10²³

Correct! Wrong!

3. How many molecules are in 1.61 x10^-3 moles of ethene?

3.73 x10²⁶

4.51 x10^-2

9.69 x10²⁰

2.67 x10^-27

Correct! Wrong!

4. How many iron ions are in 0.500 moles of Fe₂O₃?

3.01 x10²³

6.02 x10²³

1.66 x10^-24

8.30 x10^-25

Correct! Wrong!

5. How many molecules are present in 5.00 kg of O₂?

9.41 x10²⁵

1.88 x10²⁵

3.01 x10²⁴

9.41 x10²²

Correct! Wrong!

6. A sample of SO₂ contains 5.00 x10²³ molecules. How many moles are present in this sample?

0.831

1.20 x10²⁰

3.01 x10⁴⁷

53.2

Correct! Wrong!

7. How many hydroxide ions are present in 10g of Barium hydroxide?

6.02 x10²⁴

7.03 x10²³

3.51 x10²²

1.03 x10²⁵

Correct! Wrong!

8. What is the mass of one atom of nitrogen?

1.16 x10^-23

2.33 x10^-23

4.21 x10²⁴

4.30 x10²²

Correct! Wrong!

9. What is the mass of 1 molecule of BF₃?

5.32 x10^-23

8.88 x10²¹

4.08 x10²⁵

1.13 x10²³

Correct! Wrong!

10. 1 molecule of Cl₂. has a mass of 1.16 10^-22. Which isotopes are present in this molecule?

2 atoms of ³⁵Cl

2 atoms of chlorine ³⁷Cl

1 atom of chlorine ³⁵Cl and 1 atom of ³⁷Cl

Correct! Wrong!

Avogadro's number calculations

Work through the examples above again

Good attempt

You've cracked it!

Gemma Shearer