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

2

Explanation:

Since Sulphur atom has 6 valence electrons ... in which when forming a sulphur dioxide molecule ... it uses 4 valence electrons ... in which the sulphur atom shares its electrons ... in an order of 2 electrons per each oxygen atom

Hence leaving 2 valence electrons ... which are not used