Given that Δ H ∘ f [ H ( g ) ] = 218.0 kJ ⋅ mol − 1 Δ H ∘ f [ C ( g ) ] = 716.7 kJ ⋅ mol − 1 Δ H ∘ f [ CH 4 ( g ) ] = − 74.6 kJ ⋅ mol − 1 calculate the average molar bond enthalpy of the carbon‑hydrogen bond in a CH 4 molecule

Average molar bond enthalpy of C-H bond in is 415.825 kJ/mol.

Explanation:

Reaction:

Heat of reaction (energy needed to break 4 moles of C-H bond in 1 mol of ) =

        =

1 mol of contain 4 moles of C-H bonds.

So, average molar bond enthalpy of C-H bond in

     =

     = 415.825 kJ/mol

what is the general relationship between a galaxy's distance from earth and its speed?

the answer is:

the farther away a galaxy is from us, the faster it is moving away from us.

i think its 100.

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