Question

Give an example of reaction where following are involved:
(1) Heat is released
(2) Heat is absorbed
(3) Sound energy

Answer 1

Answer:

exothermic

endothermic

solution

Answer 2

Reactions

Explanation:

1) Heat is released

An exothermic reaction is a reaction in which heat is given out. So the container will feel hot in such process.

Example: Combustion of fuels such as wood, coal and oil.

CH4 + 2(O2) ---> CO2 + 2H2O + heat.

2) Heat is absorbed

An endothermic reaction is a reaction in which heat is absorbed. So the container will feel cold in such process.  

Example: Melting of ice.

NH4Cl + H2O → HCl + NH4OH

3) Sound energy

When hydrogen is ignited, it makes a loud sound as the air expands rapids and a sharp explosion is caused.

2H + O -> H2O + energy.