Answer: (C) .There are four molecules of sodium sulfite.
Explanation:
means that there are four molecules of sodium sulfite.
Molecule is defined as a group of atoms bonded together. They are smallest unit of the substance which participates in a chemical reaction.
Atom is defined as smallest unit of matter which composed of electrons , protons and neutrons.
Explanation:
Meso compounds are optically inactive stereoisomers. Despite of having chiral carbon, they do not show optical activity because it has a plane of symmetry in its structure itself. It is superposable on its mirror image.
Aldo sugars on reaction which reducing agents such as , NaBH₄ reduces the carbonyl group in the sugar to alcohol and gives corresponding alditol.
<u>The D- aldohexose which on reduction gives a meso alditol are allose and galactose. </u>
<u>The structure is shown in the image below. Thus, in allitol and galactitol formed have internal plane of symmetry which makes the optically inactive.</u>
