From their Lewis structures, determine the number of σ and π bonds in each of the following molecules or ions: (a) hydrazine, N2H4 (b) hydrogen cyanide, HCN (c) sulphur trioxide, SO3

Verified step by step guidance

1. Step 1: Draw the Lewis structure for each molecule or ion. For hydrazine (N2H4), connect the two nitrogen atoms with a single bond and attach two hydrogen atoms to each nitrogen. For hydrogen cyanide (HCN), connect the hydrogen to carbon with a single bond and carbon to nitrogen with a triple bond. For sulfur trioxide (SO3), draw sulfur in the center with three double bonds to three oxygen atoms.
2. Step 2: Identify the σ (sigma) bonds in each molecule. Sigma bonds are the first bonds formed between two atoms. In N2H4, each N-H bond and the N-N bond are sigma bonds. In HCN, the H-C bond and one of the C-N bonds are sigma bonds. In SO3, each S-O bond is a sigma bond.
3. Step 3: Identify the π (pi) bonds in each molecule. Pi bonds are the second and third bonds formed between two atoms. In N2H4, there are no pi bonds as all bonds are single. In HCN, the remaining two bonds in the C-N triple bond are pi bonds. In SO3, each S-O double bond contains one pi bond.
4. Step 4: Count the total number of σ and π bonds in each molecule. For N2H4, count the total number of sigma bonds. For HCN, count the sigma and pi bonds separately. For SO3, count the sigma and pi bonds separately.
5. Step 5: Summarize the number of σ and π bonds for each molecule. Ensure that the total number of bonds matches the number of bonds in the Lewis structure for each molecule.