The compounds \( [\text{PtCl}_2(\text{NH}_3)_4]\text{Br}_2 \) and \( [\text{PtBr}_2(\text{NH}_3)_4]\text{Cl}_2 \) constitute a pair of:
Which of the following compounds can exhibit geometrical isomerism, and why?
1) 2-butene
2) 1-butene ?
3) Pent-2-ene
4) But-2-yne