Question

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. The temperature at the start of the reaction was 23.0°C and at the end it was 19.0°C. Calculate the energy absorbed by the reaction.

Answer 1

Answer: The energy absorbed by the reaction from the water is 996 Joules.

Explanation:

Energy absorbed by the reaction or energy lost by the water to the reaction,Q.

Mass of the the reaction  ,m = 60 g

Specific heat of water = c = 4.15 J\g ^oC

Change is temperature=$\Delta T=19^oC-23^oC=-4^oC$

$Q=mc\Delta T=60 g\times 4.15 J\g ^oC\times (-4^oC)=-996 Joules$

Negative sigh indicates that energy was given by the water to the reaction.

The energy absorbed by the reaction from the water is 996 Joules.