Question

1. when an atom gains electrons, it is a) reduced b) oxidized c) ionic d) an isotope e) radioactive 55) which of the following cannot exist as a single - pair of atoms? a) oxygen b) molecular nitrogen c) sodium chloride d) a and b e) b and c

Explanation:

Step1: Recall oxidation - reduction concept

Oxidation is the loss of electrons and reduction is the gain of electrons.

Step2: Analyze the options

When an atom gains electrons, it is reduced according to the definition of reduction - oxidation reactions.

Step1: Recall atomic bonding concepts

Oxygen can exist as O₂ (a molecule with a double - bond between two oxygen atoms), nitrogen exists as N₂ (a molecule with a triple - bond between two nitrogen atoms), and sodium chloride is an ionic compound made up of Na⁺ and Cl⁻ ions and not a single pair of atoms.

Step2: Determine the answer

Sodium chloride cannot exist as a single pair of atoms.

Answer:

A. reduced