Exam code: YCH11
Select a download format for Group 7
Select an answer set to view for
Group 7
Which statement about the Group 7 elements chlorine, bromine and iodine is not correct?
boiling temperature increases down the group
reactivity increases down the group
first ionisation energy decreases down the group
electronegativity decreases down the group
Choose your answer
Was this exam question helpful?
Which silver halides are soluble in concentrated aqueous ammonia?
AgBr and AgI
AgCl and AgI
AgCl and AgBr
AgCl only
Choose your answer
Was this exam question helpful?
Which of these increases as Group 7 is descended?
oxidising ability of the molecular halogens
reducing ability of the halide ions
electrostatic attraction between the nucleus and outer shell of electrons
electronegativity of the halogen atoms
Choose your answer
Was this exam question helpful?
When iodine is dissolved in a non-polar organic solvent, the solution formed is
purple
orange
colourless
brown
Choose your answer
Was this exam question helpful?
Chlorine reacts with cold dilute aqueous sodium hydroxide.
Cl2 (aq) + 2NaOH (aq) → NaCl (aq) + NaClO (aq) + H2O (l)
Which statement about this reaction is correct?
Chlorine is only oxidised
The oxidation number of chlorine in Cl2 is −1
The oxidation number of chlorine in NaClO is 0
Chlorine is both oxidised and reduced in this reaction
Choose your answer
Was this exam question helpful?
This question is about the reaction of potassium iodide with concentrated sulfuric acid.
Which of these would not be seen?
misty fumes
black solid
yellow solid
dense white smoke
Choose your answer
One of the reaction products is the gas H2S. What is the change in oxidation number of sulfur as H2S forms?
−8
−6
−2
+6
Choose your answer
Was this exam question helpful?
Four tests used to identify ions are shown:
1 flame test
2 addition of acidified barium nitrate solution
3 addition of acidified silver nitrate solution
4 addition of sodium hydroxide solution, then testing any gas with indicator paper
Which tests could be used to positively identify the ions in ammonium chloride?
1 and 2
1 and 3
2 and 4
3 and 4
Choose your answer
Was this exam question helpful?
Solid potassium bromide reacts with concentrated sulfuric acid.
Which of these substances does not form?
bromine
hydrogen bromide
hydrogen sulfide
sulfur dioxide
Choose your answer
Was this exam question helpful?
A student adds chlorine water to an aqueous solution of an unknown potassium halide. A small volume of cyclohexane (density = 0.79 g cm–3) is then added and the mixture is shaken thoroughly.
The upper layer turns purple/violet.
Which halide was present in the original solution?
KBr
KCl
KF
KI
Choose your answer
Was this exam question helpful?
A solution containing both bromine and chlorine produces bromate ions, BrO3−, in two reactions.
Reaction 1: Br2 + H2O → HBr + HBrO
Reaction 2: 3HBrO + Cl2 → 2Cl− + BrO3− + Br2 + 3H+
Which row shows which statements are correct (✓) and which are incorrect (✗)?
Chlorine is reduced in reaction 2 | Bromine is reduced in both reaction 1 and reaction 2 | Bromine is oxidised in reaction 2 only | |
|---|---|---|---|
A | ✓ | ✗ | ✗ |
B | ✓ | ✓ | ✗ |
C | ✗ | ✓ | ✓ |
D | ✓ | ✓ | ✓ |
Choose your answer
Was this exam question helpful?
Two experiments are carried out with potassium chloride.
Experiment 1: Aqueous silver nitrate is added to aqueous potassium chloride, followed by an excess of dilute aqueous ammonia. The final observation is X.
Experiment 2: Concentrated sulfuric acid is added to solid potassium chloride. The gas produced is bubbled into aqueous potassium iodide. The final observation is Y.
Which row identifies observations X and Y?
X | Y | |
|---|---|---|
A | colourless solution | brown solution |
B | colourless solution | colourless solution |
C | white precipitate | brown solution |
D | white precipitate | colourless solution |
Choose your answer
Was this exam question helpful?
The acid HIO disproportionates in aqueous solution. In the equation, q, r, s and t are whole numbers in their lowest ratio.
qHIO (aq) → rI2 (aq) + sHIO3 (aq) + tH2O (l)
Which row gives the values of r and s?
r | s | |
|---|---|---|
A | 1 | 2 |
B | 2 | 1 |
C | 4 | 1 |
D | 4 | 2 |
Choose your answer
Was this exam question helpful?
Chlorine reacts with hot aqueous sodium hydroxide to form sodium chloride and sodium chlorate(V).
Which is the half-equation for the oxidation of chlorine in this reaction?
½Cl2 + e− → Cl−
½Cl2 + 2OH− → ClO− + H2O + e−
½Cl2 + 6OH− → ClO3− + 3H2O + 5e−
Cl2 + 6OH− → ClO3− + 3H2O + 5e−
Choose your answer
Was this exam question helpful?
80 cm3 of hydrogen chloride gas is mixed with 50 cm3 of ammonia gas. The reaction goes to completion and all volumes are measured at r.t.p.
The gas left at the end is then dissolved in water.
Which row describes the volume of gas left and the solution formed?
Volume of gas left / cm3 | Solution formed | |
|---|---|---|
A | 30 | acidic |
B | 30 | alkaline |
C | 80 | acidic |
D | 80 | alkaline |
Choose your answer
Was this exam question helpful?
0.515 g of a sodium halide, NaX, is dissolved in water. Excess aqueous silver nitrate is added, and 0.940 g of silver halide precipitate forms.
A sample of solid NaX is then warmed with concentrated sulfuric acid.
Which row identifies the halide ion and the observations with concentrated sulfuric acid?
[Ar values: Na = 23.0 Cl = 35.5 Br = 79.9 Ag = 107.9]
Halide ion | Observations with concentrated sulfuric acid | |
|---|---|---|
A | chloride | misty fumes only |
B | chloride | misty fumes and red-brown fumes |
C | bromide | misty fumes only |
D | bromide | misty fumes and red-brown fumes |
Choose your answer
Was this exam question helpful?
Astatine is below iodine in Group 7.
Solid sodium astatide, NaAt, is predicted to react with concentrated sulfuric acid in a similar way to solid sodium iodide.
A redox product is a substance formed when an element is oxidised or reduced.
Which row describes hydrogen astatide, HAt, and hydrogen sulfide, H2S, in this reaction?
HAt | H2S | |
|---|---|---|
A | not a redox product | a redox product |
B | not a redox product | not formed |
C | a redox product | a redox product |
D | a redox product | not formed |
Choose your answer
Was this exam question helpful?
2.84 g of chlorine reacts completely with excess hot aqueous sodium hydroxide.
What is the mass of the sodium salt formed in which chlorine has a positive oxidation number?
[Ar values: O = 16.0 Na = 23.0 Cl = 35.5]
0.993 g
1.42 g
2.98 g
4.26 g
Choose your answer
Was this exam question helpful?