Question
est yourself
1 Is each of the following reactions endothermic or exothermIc?
a) the temperature started at 21°C and finished at 46°C
b) the temperature started at 18°C and finished at 14°C
c) the temperature started at 19°C and finished at 25°C
2 Is each of the following reactions endothermic or exothermic?
a) burning alcono
b) thermal decomposition of iron carbonate
c) reaction of vinegar (containing ethanoic acid) with baking powder (sodium
hydrogencarbonate)
d) reaction of vinegar (containing ethanoic acid) with sodium hydroxide
3 a) Why does the temperature increase when an exothermic reaction takes
place in solution?
b) Why does the temperature decrease when an endothermic reaction takes
place in solution?
Answer
1. a) exothermic
b) endothermic
c) exothermic
2. a) exothermic
b) endothermic
c) endothermic
d) exothermic
3. a) The temperature increases because energy is released from the reaction and transferred to the surroundings.
b) The temperature decreases because energy is absorbed from the surroundings and used in the reaction.