Reactivity trends

Question 1

metal + acid

Answer 1

metal + acid –> salt + hydrogen

Question 2

Group 2 metal oxide + water

Answer 2

metal oxide + water –> OH- ions (alkaline solution)

Question 3

Solubility of hydroxides in water

Answer 3

Increases down the group

Question 4

States of halogens

Answer 4

Fluorine: gas
Chlorine: gas
Bromine: liquid
Iodine: solid

Question 5

Why do halogens increase in melting point down the group?

Answer 5

• More electrons
• Greater London forces
• Stronger bonds

Question 6

What happens to halogens in redox?

Answer 6

Reduced (they’re oxidising agents)

Question 7

Reactivity in halogens and why

Answer 7

Decreases down the group
- Needs to gain electrons
- Greater distance
- Less nuclear attraction + more shielding
- Lower reactivity

Question 8

What’s chlorine used for?

Answer 8

• Making bleach
• Water treatment (disinfectant)

Question 9

Carbonate test

Answer 9

• Add dilute nitric acid
• Bubble gas through limewaater

Question 10

Silver nitrate halide test

Answer 10

• Add AgNO3 to halide solution
• Colored precipitates are formed
• Add aq ammonia to test solubility

Question 11

Silver halide precipitate colours

Answer 11

Silver chloride: white (soluble)
Silver bromide: cream (soluble)
Silver iodide: yellow (insoluble)

Question 12

Sequence of test for anions

Answer 12

1) carbonates
2) sulfates
3) halides

Question 13

Cation test for ammonium

Answer 13

• Add aq NaOH
• Ammonia gas is produced

Question 14

Group 2 metal + water

Answer 14

metal + water –> metal hydroxide + hydrogen

Question 15

Chlorine + water

Answer 15

chlorine + water –> chloric acid + hydrochloric acid