A 28.4 g sample of an unknown compound containing carbon, hydrogen and oxygen, is burned and 54.3 g of carbon dioxide and 15.6 g of water are produced. The measured molar mass of the compound was determined to be 230.24 g/mol. Find:
a) the empirical formula of the compound
a) the molecular formula of the compound

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.

dynamic equilibrium is the answer.

they are made of gases.

they have a spherical shape.

they make energy through fusion.