Question

What is the realationship between the two terminal groups in a cumulene containing three consecutive double bonds?$(H_{2}C=C=C=C{H}_2)$

• A. $\text{They are in the perpendicular plane}$
• B. $\text{They are in same plane}$
• C. $\text{They are in two planes at}{120}^{\circ }$
• D. $\text{They are in two planes at}{109}^{\circ }$

Answer 1

The correct option is B $\text{They are in same plane}$

In odd cumulenes, the terminal groups exist in same plane. So, the two terminal groups (in a cumulene contaning three concecutive double bonds $H_{2}C=C=C{H}_2$) are in same plane. Hence correct option is b.