Question

express your answer in condensed form in order of increasing orbital energy as a string without blank space between orbitals. for example, he2s^22p^2 should be entered as he2s^22p^2. sr
express your answer in condensed form in order of increasing orbital energy as a string without blank space between orbitals. for example, he2s^22p^2 should be entered as he2s^22p^2. y

Explanation:

Step1: Find Sr's atomic number

Strontium (Sr) has an atomic number of 38, so it has 38 electrons. The noble gas preceding Sr is Krypton (Kr, atomic number 36).

Step2: Write condensed electron config

The remaining 2 electrons occupy the 5s orbital.
<Expression>
[Kr]5s^2
</Expression>

Step3: Find Y's atomic number

Yttrium (Y) has an atomic number of 39, so it has 39 electrons. The noble gas preceding Y is Krypton (Kr, atomic number 36).

Step4: Write condensed electron config

The remaining 3 electrons occupy the 5s and 4d orbitals.
<Expression>
[Kr]5s^24d^1
</Expression>

Answer:

Sr: $\boldsymbol{[Kr]5s^2}$
Y: $\boldsymbol{[Kr]5s^24d^1}$