Question

(+)-Tartaric acid and meso-tartaric acids are :

Answer 1

Tartric acid contains two asymmetric centers, but two of the "isomers" are equivalent and together are called meso which is not optically active, while the remaining two isomers are D- and L- mirror images, i.e., enantiomers. The meso form is a diastereomer of the other forms.