## Chemistry and Chemical Reactivity (9th Edition)

a) The number of moles of $NaBH_4$ is: $0.136\ g\div 37.83\ g/mol=3.595×10^{-3}\ mol$ From stoichiometry, it follows: $1.797×10^{-3}\ mol$ diborane. Using the ideal gas law and plugging in the known values, it follows: $P=nRT/V$ $P=0.016\ atm$ b) From Dalton's law: $P_{H_2}=2×P_{B_2H_4}$, so the total pressure is: $P=0.048\ atm$