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Chemistry Department
The Group 7 elements
1
Write out and complete the following sentences about the Group 7 elements.
The Group 7 elements
A
Their order of reactivity is
reactive). Chlorine is a
iodine is a grey-black
2
, chlorine, bromine and iodine are called the
C
E
G
(most reactive), chlorine,
coloured gas, bromine is a
D
F
B
.
and iodine (least
coloured liquid and
.
(a) Describe the reaction between sodium and bromine, stating any observations that
you would make.
(b) Write a word equation for this reaction.
3
What observations, if any, would you make when the following solutions are mixed? In
each case, explain your answer and write any relevant equations.
(a) A solution of chlorine in water is mixed with a solution of potassium iodide.
(b) A solution of bromine in water is mixed with a solution of potassium chloride.
(c) A solution of bromine in water is mixed with a solution of potassium iodide.
4
Write out and complete the following sentence.
Group 7 elements have similar properties because …
5
Chlorine is a Group 7 element. Sodium is a Group 1 element.
(a) State the name of the compound formed when chlorine reacts with sodium.
(b) State three uses of the compound formed when chlorine react with sodium.
6
A green gas, X, is passed through a concentrated aqueous solution of potassium iodide
in a test tube. A brown solution, Y, is formed and a grey solid, Z, is deposited at the
bottom of the tube.
(a) Identify X, Y and Z.
(b) Write a word equation for the reaction which occurs.