Question

instructions: for each of the following pairs, predict which atom has the highest first ionization energy.

1. ____ c, n
2. ____ o, s
3. ____ be, ca
4. ____ mg, al

instructions: use the flaure shown below to answer question 13

Explanation:

Step1: Determine ionization energy trends

Ionization energy increases across a period (from left to right) and decreases down a group.

Step2: Analyze each pair

• For \(C\) and \(N\): They are in the same period. Since \(N\) is to the right of \(C\), \(N\) has higher ionization energy.
• For \(O\) and \(S\): They are in the same group. Since \(O\) is above \(S\), \(O\) has higher ionization energy.
• For \(Be\) and \(Ca\): They are in the same group. Since \(Be\) is above \(Ca\), \(Be\) has higher ionization energy.
• For \(Mg\) and \(Al\): \(Mg\) has a filled \(3s\) sub - shell (\([Ne]3s^{2}\)) and \(Al\) has \(3s^{2}3p^{1}\). Removing an electron from \(Mg\)'s stable filled sub - shell is harder, so \(Mg\) has higher ionization energy.

Answer:

1. \(N\)
2. \(O\)
3. \(Be\)
4. \(Mg\)