H2SO4 + Ca(OH)2 --> CaSO4 +
H20
Balancing?

This is an acid-base reaction (neutralization): H 2SO 4 is an acid, Ca(OH) 2 is a base.

...

1H2SO4 + Ca(OH)2 → H2O + CaSO4

2H2SO4 + Ca(OH)2 → CaSO4 + HOH

3H2SO4 + Ca(OH)2 → H2O + CaOH2SO4

4H2SO4 + Ca(OH)2 → H2O + Ca(HSO4)2

5H2SO4 + Ca(OH)2 → H2O + (CaOH)2SO4

Explanation:

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.

i think it's c. i'm not sure but i think so.