Question

Q1
The order of C-H bond energies of labelled
hydrogens of following molecule is
H
H
1
H
3
H
2
O Hy > H₂>H3> H4
O Hy > H3 > H2> H4
O H3 > H2> H4> H1
O Hy > H4> H₂>H₃​

Answer 1

Answer:

2.572 is required electronegativity of carbon.

Explanation:

Given bond dissociation energies :

E(H−H)=104.2 Kcal/mol

E(C−C)=83.1 Kcal/mol

E(C−H)=98.8 Kcal/mol

Difference in electronegativity of carbon and hydrogen given by :

X

C

−X

H

=(eV)

1/2

E

(C−H)

−

2

E

C−C

+E

H−H

w.k.t, X

H

=2.1 standard value of hydrogen electronegativity also, V=

⇒X

C

−2.1=(0.208)

98.8−

2

104.2+83.1

⇒X

C

−2.1=(0.208)(2.2694)

⇒X

C

=2.572 is required electronegativity of carbon.