Final answer:
The substitution product is formed when 3-bromo-3-ethylpentane is heated in methanol.
Step-by-step explanation:
In the reaction of 3-bromo-3-ethylpentane heated in methanol, the substitution product is formed. The reaction involves the substitution of the bromine (Br) atom with a methanol (CH3OH) molecule. The product of this reaction can be represented as CH3-CH2-CH2-CH2-CH2-CH2-CH2-OH.