Further Analysis and Quantitative Chemistry

Question 1

How can metal ions be detected using the flame test?

Answer 1

barium compounds result in a green flame

calcium compounds result in a red flame

lithium compounds result in a crimson flame
-(liver is crimson)

potassium compounds result in a lilac flame

sodium compounds result in a yellow flame

Question 2

What forms white precipitates?

Answer 2

aluminium, calcium and magnesium with sodium hydroxide solution

only aluminium hydroxide precipitate dissolves in excess sodium hydroxide solution

Question 3

What forms coloured precipitates?

Answer 3

Copper(II), iron(II) and iron(III) ions form coloured precipitates with sodium hydroxide solution

Copper forms a blue precipitate

iron(II) a green precipitate
-(iron 2, goo, goo is green)

iron(III) a brown precipitate
-(irone three, tree, trees are brown)

Question 4

What forms carbon dioxide?

Answer 4

carbonate react with dilute acids to form CO2

CO2 produces a white precipitate with limewater which turns it cloudy

Question 5

How do halide ions form precipitates?

Answer 5

halide ions in solution produce precipitates with silver nitrate solution in the presence of dilute nitric acid

silver chloride is white

silver bromide is cream
(creamy grafts with ya bros)

silver iodide is yellow

Question 6

How do sulfate ions produce a white percipitate

Answer 6

Sulfate ions in solution produce a white precipitate with barium chloride solution in the presence of dilute hydrochloric acid

Question 7

How can volumes of acid and alkali solution that react with each other be measures?

Answer 7

using titration and a suitable indicator

uses a burette that contains acid

Question 8

What are the steps involved in titration calculations?

Answer 8

1) convert volumes to dm^3
e. g. 25cm^3 of HCl = 25cm/1000 = 0.025dm^3

2) use the equation : moles = concentration x volume to find the number of moles