Past Paper Higher 1

Question 1

State one difference and one similarity between the electronic structure of sodium and chlorine

Answer 1

difference : sodium has 1 electron in it’s outer shell, chlorine has 7 electrons in it’s outer shell

similarity : both have incomplete outer shells

Question 2

Sodium reacts with chlorine to produce NaCl. What happens?

Answer 2

Sodium loses one outer shell electron

Chlorine atom gains one electron

Question 3

When chlorine reacts with potassium bromide, chlorine displaces bromine.

Why is chlorine more reactive than bromine?

Answer 3

Chlorine is a smaller atom

Chlorine has less shielding

Therefore chlorine can gain an electron more easily

Question 4

What are the conditions needed for sodium chloride to conduct electricity?

Answer 4

Must be aqueous

or molten

so ions are free moving

Question 5

Give the formula of each product when Calcium carbonate. (CaCO3) is heated?

Answer 5

CaO

CO2

Question 6

What is the pH of sodium oxide?

Answer 6

14 (strong alkali)

Question 7

What is the pH of phosphorous oxide?

Answer 7

3

Question 8

What is the pH of magnesium oxide?

Answer 8

9

Question 9

What is the pH of silicon dioxide?

Answer 9

7

Question 10

Iron reacts with dilute hydrochloric acid to produce iron chloride solution and one other product?

What?

Answer 10

hydrogen

Question 11

Explain which species is reduced in the reaction between magnesium and iron chloride

3 Mg + 2 FeCl3 –> 2 Fe + 3 MgCl2

Answer 11

Fe3+
(because) reduction is gain of
electrons