Final answer:
Cyanoacetylene contains a total of three sigma bonds: one from the triple bond between two carbon atoms, one from the single bond between a carbon atom and the nitrogen atom, and one from the single bond between the hydrogen and a carbon atom.
Step-by-step explanation:
To determine the number of sigma bonds in cyanoacetylene, we must look at the types of bonds present in the molecule. Cyanoacetylene has a triple bond between two carbon atoms and a single bond between the carbon atom at one end and a nitrogen atom. A triple bond consists of one sigma bond and two pi bonds, and a single bond is always a sigma bond.
Therefore, the molecule contains:
- One sigma bond from the triple bond
- One sigma bond from the single bond between carbon and nitrogen
Additionally, cyanoacetylene has a sigma bond between the carbon atom and any hydrogen atoms attached to it.
From the basic structure of cyanoacetylene (H-C≡C-CN), we have:
- One sigma bond between the hydrogen and carbon atom
- Three sigma bonds in total for the entire molecule