Practice Reactivity 1. What drives chemical reactions? with authentic IB Chemistry exam questions for both SL and HL students. This question bank mirrors Paper 1A, 1B, 2 structure, covering key topics like atomic structure, chemical reactions, and organic chemistry. Get instant solutions, detailed explanations, and build exam confidence with questions in the style of IB examiners.
Paper
Level
Question 1
SLPaper 2
When ethane () reacts with chlorine gas under UV light, a substitution reaction occurs. This involves breaking the bond to form free radicals before new bonds are made.
1.[1]
Identify the bond being broken in chlorine gas.
2.[2]
State whether breaking this bond is endothermic or exothermic and justify your answer.
3.[2]
Define the term bond enthalpy.
4.[1]
Suggest why ultraviolet light is needed to start this reaction.
5.[1]
State the bond formed between the carbon atom and the incoming chlorine atom during the substitution.
Question 2
HLPaper 2
Melting ice is a spontaneous process at room temperature.
1.[1]
Predict the sign of for the melting of ice.
2.[1]
State one reason for this prediction.
3.[2]
Explain in terms of particle arrangement why entropy increases during melting.
Question 3
HLPaper 2
Reaction:
,
1.[2]
Calculate at .
2.[2]
Calculate temperature where .
Question 4
SLPaper 2
A candle is burned in a closed jar with limited oxygen. Over time, black soot forms on the glass, and the flame goes out.
1.[1]
Define incomplete combustion.
2.[1]
Write a balanced chemical equation for the incomplete combustion of methane forming carbon monoxide.
3.[1]
State another possible product of incomplete combustion besides carbon monoxide.
4.[2]
Suggest why incomplete combustion is dangerous in enclosed spaces.
5.[1]
Compare the energy released in complete and incomplete combustion of the same fuel.
Question 5
SLPaper 2
Ammonia is formed by the Haber process:
The diagram below shows the energy profile of this reaction.
1.[1]
State what is meant by the term activation energy.
2.[2]
Identify whether the reaction is exothermic or endothermic and justify your answer using the diagram.
3.[1]
Suggest one reason why a high temperature is required for this reaction to proceed at a practical rate.
4.[2]
Explain how the use of a catalyst would affect the energy profile diagram.
5.[2]
The Haber process is a reversible reaction. State and explain one condition used in industry to increase the yield of ammonia.
Question 6
HLPaper 2
Ammonia synthesis:
,
1.[3]
Calculate at .
2.[1]
State whether the reaction is spontaneous.
3.[1]
Predict the effect of increasing temperature on spontaneity.
Question 7
HLPaper 1A
Which equation represents the standard enthalpy of atomization of bromine, ?
Question 8
SLPaper 1A
What is the heat change, in kJ, when 100.0 g of aluminium is heated from 19.0 °C to 32.0 °C?
Specific heat capacity of aluminium: 0.90
Question 9
SLPaper 1A
Which change of state is exothermic?