Final answer:
A compound with 2 stereocenters can have a maximum of 4 different stereoisomers as determined by the formula 22. Some compounds may have fewer stereoisomers due to the presence of achiral meso compounds.
Step-by-step explanation:
The question is related to the number of different stereoisomers that can exist for a compound with 2 stereocenters. The maximum number of stereoisomers for a chiral compound is determined by the formula 2n, where n is the number of chiral centers. In the case of a compound with two chiral centers, we apply the formula 22 which equals 4. Therefore, there can be a maximum of 4 stereoisomers for a compound with two stereocenters.
It is important to note that while some compounds with two chiral centers, such as erythrose, do have four stereoisomers, in certain cases, such as tartaric acid, there might be fewer because of the presence of a meso compound, which is achiral. However, the question asks for the maximum number, so the actual presence of a meso compound does not change the answer in this case.