Why do doctors prescribe amoxicillin instead of penicillin for tonsiitis?

amoxicilin is a semi-synthetic form of penicillin. After

the penicillin is extracted, some of it is converted to amoxicillin. penicillin is primarily for gram+

bacteria while amoxicillin is effective against both gram positive and gram negative bacteria.Amoxicillin is better absorbed than penicillin as it can withstand the acidity of stomach juice better than penicillin releasing more antybiotics in to blood stream.