Question

25 apply concepts use the periodic table to write the noble gas configuration for strontium (sr).

Explanation:

Step1: Locate strontium in periodic table

Strontium (Sr) has atomic number 38.

Step2: Identify the nearest noble - gas before Sr

The nearest noble - gas before Sr is krypton (Kr) with atomic number 36.

Step3: Write the noble - gas configuration

The noble - gas configuration of Sr is [Kr]5s².

Answer:

[Kr]5s²