Which feature of a balanced chemical equation demonstrates the law of conservation of mass?
A. It has equal numbers of each type of atom in its reactants and
products.
OB. It has a reaction arrow between the products and reactants of a
chemical reaction.
OC. It shows the coefficients and subscripts of each formula shown in
the equation.
D. It shows the chemical formula for each substance in its reactants
and products

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.

3 hours because it is a decent distance.