Topic 4, Part 2 - Chemical Changes

Question 1

what metals will react with water

Answer 1

potassium, sodium, lithium and calcium

Question 2

how can some metals be extracted by reduction by carbon

Answer 2

you can use carbon for reduction of the oxygen

Question 3

what metals can be extracted using electrolysis

Answer 3

any element in the reactivity series above carbon

Question 4

what metals can be extracted by reduction using carbon

Answer 4

any metal below carbon can

Question 5

how does carbon take away oxygen in reduction (iron)

Answer 5

in a blast furnace and the iron oxide is reduced to make iron. this is because its less reactive

Question 6

what is electrolysis

Answer 6

it is when a current is passed through an electrolyte (molten or dissolved ionic compound). ions move to electrode

Question 7

where do positive ions move to in electrolysis (metal or non-metal)

Answer 7

positive metals move to the cathode (-ve electrode) and gain electrons (reduced)

Question 8

where do negative ions move to in electrolysis (metals or non-metals) (process)

Answer 8

negative non-metals move to the anode (+ve electrode) and lose electrons (oxidised)

Question 9

what is an aqueous solution

Answer 9

it is a solution with water in it

Question 10

how does aqueous solution affect the electrolysis

Answer 10

as well as ions in ionic compound, there are hydrogen ions (H+) and hydroxide ions (OH-) in the water

Question 11

at the cathode, if H+ and metal ions are present what will be produced if the metal that is formed is more reactive and less reactive

Answer 11

more reactive -hydrogen gas will produce.

less reactive - a solid layer of the pure metal

Question 12

at the anode, if OH- and halide ions are present what will be produced halide is there or not.

Answer 12

if halide is present - chlorine, bromine or iodine

if halide is not present - ions discharged and make oxygen