Question

question 3
1 point
ethene and acetylene are simple examples of double and triple bonds. how many sigma and pi bonds there are for each compound? (reference p 267 of your textbook.) duplicate answers see word doc
a ethene: 5 sigma and 2 pi; acetylene: 3 sigma and 3 pi
b ethene: 3 sigma and 1 pi; acetylene: 2 sigma and 2 pi
c ethene: 3 sigma and 4 pi; acetylene: 3 sigma and 3 pi
d ethene: 5 sigma and 1 pi; acetylene: 3 sigma and 2 pi

Explanation:

• Ethene (\(C_2H_4\)):
• The structure is \(H_2C = CH_2\).
• Each \(C - H\) bond is a sigma (\(\sigma\)) bond. There are \(4\) \(C - H\) bonds.
• The \(C = C\) double - bond consists of \(1\) \(\sigma\) bond and \(1\) \(\pi\) bond.
• Total \(\sigma\) bonds: \(4+1 = 5\). Total \(\pi\) bonds: \(1\).
• Acetylene (\(C_2H_2\)):
• The structure is \(HC\equiv CH\).
• Each \(C - H\) bond is a \(\sigma\) bond. There are \(2\) \(C - H\) bonds.
• The \(C\equiv C\) triple - bond consists of \(1\) \(\sigma\) bond and \(2\) \(\pi\) bonds.
• Total \(\sigma\) bonds: \(2 + 1=3\). Total \(\pi\) bonds: \(2\).

Answer:

D. Ethene: 5 sigma and 1 pi; Acetylene: 3 sigma and 2 pi