Please help:
An object rolled 15m/s for 3 seconds. How far did it roll?

1. since energy is released int the water bath, then the reaction is exothermic

2. since energy is released into the water bath, the temperature of the water bath will go up.

3. the system does work on the piston, therefore, the piston will move out.

4 since the reaction is exothermic, heat will flow out of the  system (gas mixture)

5. 493 kJ

Explanation:

Exothermic reactions are those reactions that liberate heat to their surrounding. The reverse is an endothermic reaction. If energy is released into the surrounding environment (water bath in this case), then the temperature of the surrounding environment will go up.

A system does work on its environment by expansion of the gas within the cylinder, which forces the piston out. In the case where work is done on the system by the environment, the piston moves inwards due to the shrinking of  the volume of the gas within it.

The gas mixture will lose heat since it reacts exothermically.

From thermodynamics,

Q = U + W

where

Q = total heat in the system

U = the internal energy of the system ( negative if exothermic) = -368 kJ

W = work done by the system (negative if work is done on the system) = -125 kJ

imputing values,

Q = -368 + (-125) = -368 - 125 = -493 kJ

the negative sign shows that 493 kJ of heat is lost from the system in total