1. 1
   A student investigates the Group 1 alkali metals lithium, sodium and potassium. Small, freshly cut pieces of each metal are added, one at a time, to separate troughs of water and the reactions are observed.

   (a)

   Which gas is produced when a Group 1 metal reacts with water?

   [1 mark]

   • AHydrogen
   • BOxygen
   • CCarbon dioxide
   • DChlorine

   (b)

   What is the charge on a Group 1 metal ion formed when the metal reacts to form an ionic compound?

   [1 mark]

   • A-1
   • B+2
   • C+1
   • D+3

   (c)

   Describe two observations the student would expect to see when the piece of potassium is added to the water.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A technician dissolves separate samples of lithium hydroxide, sodium hydroxide and potassium hydroxide in water, then tests each resulting solution with universal indicator solution.

   (a)

   What colour would universal indicator turn when added to a solution of an alkali metal hydroxide?

   [1 mark]

   • ARed
   • BPurple/blue
   • CGreen
   • DOrange

   (b)

   Which statement correctly describes the hydroxides of Group 1 metals?

   [1 mark]

   • AThey do not react with water
   • BThey are insoluble in water
   • CThey dissolve in water to form acidic solutions
   • DThey dissolve in water to form alkaline solutions

   (c)

   Explain, in terms of the ions present, why the solutions of Group 1 metal hydroxides tested by the technician are alkaline.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A student places small, equal-sized pieces of lithium, sodium and potassium, each freshly cut and taken from storage under oil, into separate beakers of water and records the time taken for each metal to completely react.

   (a)

   Describe the trend in reactivity shown by lithium, sodium and potassium in this experiment, and state which metal reacted fastest.

   [3 marks]

   (b)

   Describe the general physical properties of Group 1 metals shown in this experiment and explain why they are stored under oil rather than in air.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   In a demonstration, a teacher reacts small pieces of several Group 1 metals with water and with chlorine gas, and asks students to explain the properties and reactions observed.

   (a)

   Describe in detail what would be observed when a small piece of a Group 1 metal is added to water, including a word equation for the reaction, and explain how the vigour of this reaction changes for different Group 1 metals.

   [6 marks]

   (b)

   Explain why Group 1 metals are described as having unusually low densities and soft textures compared with other metals, and describe the type of compound formed, and its typical properties, when a Group 1 metal reacts with a non-metal such as chlorine.

   [6 marks]

   Total for question 4: 12 marks

End of questions