5. Co-ordination chemistry — Chemistry STD 12 Science — Question

Statement $II :$ As the size of the elements $\mathrm{F}, \mathrm{Cl}, \mathrm{Br}, \mathrm{I}$ increases down the group, the bond strength of $\mathrm{HF}$, HCl, HBr and HI decreases and so the acid strength increases.

In the light of the above statements, choose the correct answer from the options given below.

$(I)$ Only compounds with chiral centers can be optically active

$(II)$ Absence of elements of symmetry is the reason for a molecule's optical activity

$(II)$ All organic compounds contain carbon & hydrogen

$(IV)$ Different cannonical forms of a molecule represent the actual structures of a molecule which has resonace in it