Question

1. List five exothermic reactions that are going on around you. (10 points)

Think about chemical reactions in which substances become colder, which

means that they are releasing heat. Be sure to include only chemical reactions,

Answer 1

Exothermic reactions are those reactions in which a system releases its heat energy to surroundings whereas during endothermic reactions a system absorbs heat energy from surroundings.

Explanation :

Five exothermic reactions that are going on around us

a) Making of ice cubes

b) Rusting of iron

c) Nuclear fission reaction

d) Cellular respiration

e) Condensation of water vapor to form rain.

Following are some endothermic reactions;

1) Photosynthesis
`6CO_(2)+12H_(2)O\xrightarrow[sunlight]{chlorophyll}C_(6)H_(12)O_(6)+6H_(2)O+6O_(2)`

2) Mixing of water in Ammonium Nitrate
`NH_(4)NO_(3)(s)\overset{H_(2)O(l)}{\rightarrow}NH^{_(3)(aq)}+H_(3)O^(+)`