Question

coulombs law problems: 1. which of the three elements has the least amount of attractive force? a. br b. cl c. i 2. which of the three elements has the most amount of attractive force? a. si b. p c. s

Explanation:

1. For Question 1:

• Atomic size increases down a group. As atomic size increases, the distance between the nucleus and the outermost electrons increases.
• According to Coulomb's law (\(F = k\frac{q_1q_2}{r^{2}}\), where \(F\) is the force, \(k\) is a constant, \(q_1\) and \(q_2\) are charges, and \(r\) is the distance), as \(r\) (distance) increases, the attractive force (\(F\)) between the nucleus (positive charge) and electrons (negative charge) decreases.
• Among \(Br\), \(Cl\), and \(I\), \(I\) is the largest (as it is lower in the halogen group). So, it has the least attractive force.

1. For Question 2:

• Across a period (from left to right), the atomic number increases. The number of protons in the nucleus increases (more positive charge), and the electrons are added to the same shell (so \(r\) - distance from the nucleus to outermost electrons does not increase much).
• According to Coulomb's law (\(F = k\frac{q_1q_2}{r^{2}}\)), as \(q_1\) (nuclear charge) increases (while \(r\) is relatively constant), the attractive force (\(F\)) increases.
• Among \(Si\), \(P\), and \(S\), \(S\) has the highest atomic number (more protons in the nucleus for the same - shell electrons). So, it has the most attractive force.

Answer:

1. C. I
2. C. S