The total number of 'sigma' and 'Pi' bonds in 2-oxohex-4-ynoic acid is ______

We need to find the total number of sigma and pi bonds in 2-oxohex-4-ynoic acid.

First, we draw its structure: 2-oxohex-4-ynoic acid is a 6-carbon chain with:

- Position 1: -COOH (carboxylic acid)

- Position 2: =O (oxo/keto group)

- Position 4-5: triple bond (ynoic = alkyne)

Thus, the structure is HOOC-CO-CH₂-C≡C-CH₃.

Next, we count the sigma bonds:

- O-H: 1 sigma

- C1=O (COOH): 1 sigma + 1 pi

- C1-O(H): 1 sigma

- C1-C2: 1 sigma

- C2=O: 1 sigma + 1 pi

- C2-C3: 1 sigma

- C3-H (×2): 2 sigma

- C3-C4: 1 sigma

- C4≡C5: 1 sigma + 2 pi

- C5-C6: 1 sigma

- C6-H (×3): 3 sigma

Summing these, the total number of sigma bonds is 1 + 1 + 1 + 1 + 1 + 1 + 2 + 1 + 1 + 1 + 3 = 14, and the total number of pi bonds is 1 + 1 + 2 = 4.

Therefore, the total number of sigma and pi bonds is 14 + 4 = 18, so the answer is 18.