If solar panels are placed in the Mojave Desert in California that generate 100 megawatts on a 1.3-square-mile site with an average of 7.50 hours of productive daylight each day, how many tons of coal are equivalent to the energy produced in one day by the solar panels? (One ton of coal will produce 26.6 gigajoules of energy 1 Watt 1 J/s.)

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

sure im new too!

explanation: