Question

Calculate the electronegativity of carbon if $E_{{H}-{H}}=$104.2 kcal mol^-1, $E_{{C}-{C}}=$ 83.1 kcal mol^-1, $E_{{C}-{H}}=$ 98.8 kcal mol^-1, $\chi_{{H}}=$ 2.1

Answer 1

SOLUTION : We know that, $\chi_{{C}}-\chi_{{H}}=0.208 \sqrt{\Delta}$

$\Delta=  E_{C-H}-\sqrt{E_{C-C} \times E_{H-H}}$

$=  98.8-\sqrt{83.1 \times 104.2}=98.8-93.05=5.75$

$\therefore \quad  \chi_{{C}}-\chi_{{H}}=0.208 \sqrt{5.75}=0.498$

$\chi_{{C}}=0.498+\chi_{{H}}=0.498+2.1$

$=2.59 \approx 2.6$