10 minutes maximum! (can you do it in 5?)
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1. Chemical reactions in which heat energy is given out are described as …..
- A. ..exothermic and produce a temperature rise in solution
- B. ..exothermic and produce a temperature drop in solution
- C. …endothermic and produce a temperature rise in solution
- D. ..endothermic and produce a temperature drop in solution
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2. The table below gives information about the temperature changes in 3 reactions:
Reaction |
Initial temperature / oC |
Final temperature / oC |
I |
25.6 |
32.4 |
II |
22.1 |
19.3 |
III |
21.5 |
48.8 |
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The reactions which are exothermic are:
- A. I and II
- B. I and III
- C. II only
- D. I, II and III
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3. Which of the following types of chemical reactions are always endothermic ?
- A. Combustion
- B. Neutralisation
- C. Displacement
- D. Thermal Decomposition
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Q4-6 refer to the following reaction profile:

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4. This diagram represents the reaction profile for an …
- A. exothermic reaction as the products are at a lower energy level than the reactants.
- B. exothermic reaction as the products are at a higher energy level than the reactants.
- C. endothermic reaction as the products are at a lower energy level than the reactants.
- D. endothermic reaction as the products are at a higher energy level than the reactants.
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5. The enthalpy change (energy change) for this reaction is correctly labelled by line
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6. Line D represents ….
- A. the enthalpy (energy) change for the reaction.
- B. the energy needed to break the bonds in the reactants.
- C. the energy released on forming bonds in products.
- D. the activation energy for the reaction.
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Q7 – 10. Water at 25 °C was used to dissolve ammonium nitrate (NH4NO3).
The ammonium nitrate disappeared and a temperature of 21°C was recorded immediately afterwards.
The student used a polystyrene cup to carry out this experiment as shown here. |
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7. The reason for using a polystyrene cup rather than a beaker is that a polystyrene cup is…..
- A. ….not breakable
- B. …. cheaper than a beaker
- C. ….a good insulator of heat
- D. ….a good conductor of heat
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8. The student correctly concluded that the dissolving of ammonium nitrate was …
- A. exothermic because the temperature decreased
- B. endothermic because the temperature decreased
- C. exothermic because the ammonium nitrate disappeared
- D. endothermic because the ammonium nitrate disappeared
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9. Which of the following energy level diagrams correctly represents this reaction?

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10. Estimate the temperature of the solution if the volume of water was halved but the same mass of ammonium nitrate used.
- A. 17°C
- B. 21°C
- C. 23°C
- D. 25°C
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