How many total valence electrons are not bonding for the central atom in the molecule of sulfur dioxide? none, 1, 2, 3, 4

The number of valence electrons that are non-bonding for sulfur atom are 2.

Explanation:

Valence electrons are defined as the electrons that are present in outermost shell of an atom.

Non-bonded electrons are defined as the electrons that do not participate in the bonding. The pair of these electrons are known as lone pairs. They are determined by lewis dot structure of compound.

To calculate the hybridization of SO_2, we use the equation:

where,

V = number of valence electrons present in central atom  (S) = 6

N = number of monovalent atoms bonded to central atom  = 0

C = charge of cation  = 0

A = charge of anion = 0

Putting values in above equation, we get:

The number of electron pair around the central metal atom are 3. This means that the hybridization will be

The number of bonded electrons of the compound = 8

Number of non-bonded electrons around the central metal atom which is sulfur = 2

Hence, the number of valence electrons that are non-bonding for sulfur atom are 2.

I do NOT agree with that statement; photosynthesis and cellular respiration are simply two different processes. This does not mean that they are necessarily opposites. However, their chemical reaction-equations are opposite of each other. The processes themselves are similar.