Final answer:
The bond line formula for CH3(CH2)3CHO, or pentanal, is depicted as a straight line with four vertices for the carbons in the butyl chain and a double line for the aldehyde group. The carbons have sp3 or sp2 hybridization with tetrahedral and trigonal planar geometries, respectively.
Step-by-step explanation:
The bond line formula for the molecule CH3(CH2)3CHO, also known as pentanal, can be represented in bond line notation. This notation simplifies the drawing of organic structures by denoting carbon atoms as the vertices (ends and bends) of lines and hydrogen atoms are implied wherever carbon makes fewer than four bonds. The bond line formula for pentanal is a straight line with four vertices, representing the carbons of the butyl chain, and a double line at the end vertex representing the aldehyde group (CHO). The molecular geometry at each carbon atom in this molecule varies, where the first four carbons in the chain (from CH3- to -CH2-) are sp3 hybridized with tetrahedral geometry and bond angles of approximately 109.5 degrees. The terminal carbon with the CHO group has sp2 hybridization, with a trigonal planar arrangement and bond angles of about 120 degrees.