What volume does 43.5 g of n2 occupy at stp? (r = 0.08206 l⋅atm/mol⋅k)?

V = n·R·T / p.
V(N₂) = 1.55 mol · 0.08206 L·atm/mol·K · 273 K / 1.00 atm.
V(O₂) = 34.72 L.

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.

quartz

explanation: