Question

1. Methylhydrazine (N₂H₃CH₃) is a common liquid propellant used in rocket fuels. Look for the standard molar enthalpies of formation of the reactants and products (you may use the uploaded files or search elsewhere for this). Calculate the ∆H^o for the reaction.

• N₂H₃CH_{3 (l)} + N₂O_{4 (l)} ---> H₂O _(g) + N_{2 (g)} + CO_{2 (g)}

Answer 1

Solution.

$Q(cal.) = Q(reac.)$

$Q(cal.) = C(cal.) × \Delta T = 113.013 kJ$

$Q(reac/mol) = \frac{Q(reac.)}{n(CH6N2)}$

$n(CH6N2) = \frac{m(CH6N2)}{M(CH6N2)}$

$n(CH6N2) = \frac{4.00}{46.1} = 0.09 \ mol$

$Q(reac/mol) = \frac{113.013 \times 10^3}{0.09} = 1.30 \times 10^6 \ J/mol$

Answer:

$Q(reac/mol) = 1.30 \times 10^6 \ J/mol$