Ethyne (hcch) does not show ir absorption in the region 2000 -2500 cm because: (a) c-h stretches occur at lower energies. (b) cc stretches occur at about 1640 c

Ethyne (HCCH) does not show IR absorption in the region 2000 -2500 cm because: (a) C-H stretches occur at lower energies. (b) CC stretches occur at about 1640 cm (c) There is no change in the dipole moment when the CC bond in ethyne stretches. (d) there is a change in the dipole moment when the CC bond in ethyne stretches.