Question

The bond enthalpy of the H-1 bond is 295 kJ/mol. What is the AH value when the bonds in 0.5 mole of HI are broken?

Answer 1

• H-I bond enthalpy=295KJ/mol

So

• No of moles=0.5

Now total enthalpy:-

• ∆H=Bond enthalpy×Moles
• ∆H=0.5(295)
• ∆H=147.5KJ

Answer 2

Given data:

• H-I bond enthalpy = 295KJ/mol

• No. of moles = 0.5

• change in bond enthalpy (∆H) = ?

Solution:

The standard formula for calculating change in bond enthalpy (∆H) is given by,

$\longrightarrow\rm{∆h = bond \: enthalpy \times moles}$

$\longrightarrow\rm{∆h =0.5 \times 295}$

$\longrightarrow\rm{∆h = 147.5 \: KJ}$

The value of ∆H is 147.5KJ