MCQ
If a mole of ${H_2}$ molecule is heated to high temperature the following reaction takes place
- ✓${H_2}(g) + 436\,kJ = H(g) + H(g)$
- B${H_2}(g) + 820\,kJ = 2{H_2}(g)$
- C$2{H_2}(g) + 436\,J = 2{H_2}$
- D${H_2} + {H_2} = {H^ + } + {H^ + }$
✓
Answer
Correct option: A.
${H_2}(g) + 436\,kJ = H(g) + H(g)$
a
The amount of energy required to break $H - H$ bond of $1\, mole$ of gaseous hydrogen is $436 \,kJ\, mol ^{-1}$. This is known as bond dissociation enthalpy.
The amount of energy required to break $H - H$ bond of $1\, mole$ of gaseous hydrogen is $436 \,kJ\, mol ^{-1}$. This is known as bond dissociation enthalpy.
$H _2( g )+436\, kJ\,mol ^{-1} \rightarrow H ( g )+ H ( g )$
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