Answer
The correct structure for each compound is written below:
Work Step by Step
Question a: Step 1 - Here, No. of C in straight chain will be 8 (because 'oct' means 8). Draw 8 C in a straight chain and join them with single bond and numbering the C from 1 to 8 from left side to right side. Find the ending name. Here, the ending name is ‘yne’. That means a triple bond is present in the compound. The number ‘3’ in 3-octyne suggests that the triple bond will be between no. 3 and no. 4 Carbon. Step 2- place a triple bond between no. 3 and no. 4 Carbon. The remaining valency of Carbon is then fulfilled by H in step 3.
Question b: step 1 - find the no. of C in straight chain. ‘pent’ means 5. Draw 5 Carbons in a straight chain and join them with single bond and numbering every carbon from left to right. Step 2- place a double bond (because ending name 'ene') in between no. 1 and no. 2 Carbon (1-pentene). Step 3- remaining valency of C will be fulfilled by H.
Question c: Step 1 - Draw 5 Carbons in a straight chain and join them with single bond (because ‘pent’ means 5) and numbering them from left to right. Step 2- place triple bond (because ending name 'yne') in between no. 1 and no. 2 Carbon. Step 3- place two methyl group in no. 3 Carbon (as the name suggests 3,3-dimethyl) . In step 4, fill the remaining valency with H.
Question d: Step 1 - draw 8 C in a straight chain and join them with single bond (‘oct’ means 8) and numbering them from left to right. Step 2, place double bond (because ending name 'ene') in between no. 2 and no. 3 Carbon. In step 3, place two one methyl group in no. 3 Carbon and one ethyl group in no. 4 Carbon (as the name suggests 4-ethyl-3-methyl). In step 4, the remaining valency will be filled with H. See every steps in picture below:
