The gas hydrazine, ${\mathrm{N}}_2{\mathrm{H}}_4$, burns in oxygen like this:

Is the reaction exothermic, or endothermic?

(The bond energies in $\mathrm{kJ} /\mathrm{mole}$ are: $\mathrm{N}-\mathrm{H}$ $391$; $\mathrm{N}-\mathrm{N} 158$; $\mathrm{N}\equiv \mathrm{N} 945$; $\mathrm{O}-\mathrm{H} 464$; $\mathrm{O}=\mathrm{O} 498$)

Where is energy transferred from, and to?

Comment on the suitability of hydrazine as a fuel.

(The bond energies in $\mathrm{kJ} /\mathrm{mole}$ are: $\mathrm{N}-\mathrm{H}$ $391$; $\mathrm{N}-\mathrm{N} 158$; $\mathrm{N}\equiv \mathrm{N} 945$; $\mathrm{O}-\mathrm{H} 464$; $\mathrm{O}=\mathrm{O} 498$)

Hydrogen and bromine react reversibly:

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Add more hydrogen will favour the formation of more hydrogen bromide?

Hydrogen and bromine react reversibly:

${\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{Br}}_2\left(\mathrm{g}\right)\rightleftharpoons 2\mathrm{HBr}\left(\mathrm{g}\right)$

Remove bromine will favour the formation of more hydrogen bromide?

Hydrogen and bromine react reversibly:

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Remove the hydrogen bromide as it forms will favour the formation of more hydrogen bromide?

Hydrogen and bromine react reversibly:

${\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{Br}}_2\left(\mathrm{g}\right)\rightleftharpoons 2\mathrm{HBr}\left(\mathrm{g}\right)$

Explain why increasing the pressure will have no effect on the amount of product formed.

Hydrogen and bromine react reversibly:

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However, the pressure is likely to be increased, when the reaction is carried out in industry. Suggest a reason for this.