Question

How many optical isomer will the tartaric acid show?

• A. $3$
• B. $4$
• C. $0$
• D. $2$

Answer 1

The correct option is A $3$

The molecule has an element of symmetry and n is even. The number of d and l forms $a=2^{n-1}$

Meso form, $m=2^{(\frac{n}{2}-1)}$

Total $=a+m$

$n=2$

$a=2^{n-1}=2^{2-1}$

$m=2^{1-1}=2^o=1$

Total $=2+1=3$.