9. calculate the standard enthalpy of the 3rd reaction using the given data: a, h° = +52.96 kj/mol afh= -483.64 kj/mol h2s)+i202 hi 2 h2g)+o2ig)2 h2o() 4 hig+o2lg)2 12)+2 h2o(e (1) (2) (3) a, h° =? 10. calculate the internal energy change for reaction (3) in the previous problem.

-586.56 kJ/mol is the standard enthalpy of the 3rd reaction.

Explanation:

...[1]

...[2]

..[3]

The unknown standard enthalpy of third reaction can be calculated by using Hess's law:

The law states that 'the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps'.

[2] - 2 × [1] = [3]

The standard enthalpy of the 3rd reaction is -586.56 kJ/mol.The negative sign indicates that energy is released during this reaction.

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.