Question

the table below shows the distance between the atoms in an atom pair. all four pairs of atoms have the same amount of electric charge.

pair of atoms	distance between the atoms
c & d	6 units
p & q	2 units
x & y	8 units

which pair of atoms are repelled from each other with the most force?
a. pair c & d
b. pair a & b
c. pair x & y
d. pair p & q

Explanation:

Step1: Recall Coulomb's law

The electrostatic force between two charged particles is inversely - proportional to the square of the distance between them when the charges are constant. $F = k\frac{q_1q_2}{r^2}$, where $q_1 = q_2$ (same charge in all pairs) and $k$ is a constant. So, the smaller the distance $r$, the larger the force $F$.

Step2: Compare the distances

We have the distances: A & B: 4 units, C & D: 6 units, P & Q: 2 units, X & Y: 8 units.

Answer:

D. pair P & Q