1. With the aid of a Hess cycle, determine the enthalpy of the decomposition reaction of sodium nitrate, NaNO3 to sodium nitrite, NaNO2 and oxygen, O2. [5] Enthalpy of formation of NaNO3 = -468 kJ/mol
Enthalpy of formation of NaNO2 = -369kJ/mol

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

Complete the sentences to best explain the ranking.match the words below to the appropriate blanks in the sentences.a less polar bondhigher molar massion-dipole forcesstronger intermolecular forcesdipole-dipole forcesdispersion forceshydrogen bonding1. h2s and h2se exhibit the following intermolecular forces:.2. therefore, when comparing h2s and h2se the one with a has a higher boiling point .3. the strongest intermolecular force exhibited by h2o is . therefore, when comparing h2se and h2o the one with has a higher boiling point.

The mass of a proton is approximately equal to the mass of