Question

If at 298 K the bond energies of C-H,C-C,CEC and H -H bonds are respectively 414, 347.
ol3 and 435 kJ mol-, the value of enthalpy change for the reaction
HC == CH2(e) + H21.→ HC - CH3() at 298 K will be:
a) + 250kJ
b) - 250kJ
c) + 125kJ
d) - 125kJ​

Answer 1

-125kgJ is the correct ans