End Of Unit Questions

Question 1

There are two main types of chlorine atom, Cl 35 and Cl 37.

How is an atom of Cl 35 different to an atom of Cl 37?

Answer 1

The Cl 37 has 2 more neutrons than Cl 35

Question 2

Hydrogen and iodine react to make hydrogen iodide. The equation for the reaction is H2 + I2 –> 2HI. What type of reaction is this?

Answer 2

Reversible

Question 3

What substances in foods can be detected by paper chromatography?

Answer 3

Artificial colours

Question 4

What is the relative formula mass of magnesium fluoride, MgF2?

Answer 4

62

Question 5

What is the mass of one mole of aluminium oxide, Al2O3?

Answer 5

102g

Question 6

What is the percentage by mass of copper (II) carbonate, CuCO3?

Answer 6

51.4%

Question 7

A student made some magnesium oxide by burning magnesium in air. The student obtained a yield of 55%. Suggest 2 reasons why the yield was less than 100%.

Answer 7

• The magnesium didn’t finish reacting
• reacted with other substances in the air
• magnesium oxide wasn’t collected or was lost

Question 8

What is the empirical formula of vanadium oxide that contains 56% of vanadium?

Answer 8

V2O5

Question 9

Calculate the mass of zinc chloride that you can make from 6.5g of zinc. Zn + 2HCl –> ZnCl2 + H2

Answer 9

13.6g

Question 10

Calculate the percentage yield if 9g of MgSO4 was made from 4g MgO

Answer 10

75%

Question 11

What information can be obtained from the molecular ion peak in a mass spectrum?

Answer 11

Relative formula mass of the compound

Question 12

There are two main types of chlorine atom, Cl 35 and Cl 37.

What name is used for these two types of atom?

Answer 12

Isotopes