Consider a power plant that uses natural gas as a fuel to generate electricity. if there are 10,000 j of chemical energy contained within a specified amount of natural gas, then the amount of electricity that could be produced would be

Something less than 10,000 J, depending on the efficiency of the generator.

Explanation:

By the first law of the thermodynamics, we know that energy can't be created or destroyed, so it must be conserved, and only transformed, as heat, work or internal energy. So, the energy generated can't be higher than 10,000 J.

By the second law of thermodynamics, we know that a machine can't convert 100% of the energy in an exclusively another form (heat in work for example). So, it's not possible that the generator converts all the 10,000 J of chemical energy in work to move the turbines to produce electricity.

So, we can conclude that the energy must be less than 10,000 J, and its exact value depends on the efficiency of the generator, which can't be 100%.

The amount of electricity that could be produced would be less than 10,000 Joules.

Explanation:

The energy that will be produced will be less than 10,000 J because that is no machine will 100% efficiency in reality. The energy loss is due to:

1. Combustion efficiency of the gas.

2. Heat loss in conversion process.