Answer: Pair 1 has Mg and Sr, Pair 2 has Kr and Ne, Pair 3 has As and P.
Step-by-step explanation:
A periodic table is a group of elements presented in a tabular form where elements are arranged in a series of 7 rows and 18 columns.
The vertical columns are known as groups and horizontal rows are known as periods.
The elements having similar chemical properties are arranged in one group.
Magnesium (Mg) is the 12th element of periodic table placed at Group 2 and Period 3
Strontium (Sr) is the 38th element of periodic table placed at Group 2 and Period 5
Krypton (Kr) is the 36th element of periodic table placed at Group 18 and Period 4
Neon (Ne) is the 10th element of periodic table placed at Group 18 and Period 2
Arsenic (As) is the 33rd element of periodic table placed at Group 15 and Period 4
Phosphorus (P) is the 15th element of periodic table placed at Group 15 and Period 3
As magnesium and strontium are present in the same group, they will have similar chemical properties. Similarly, krypton and neon will form the second pair. Likewise, arsenic and phosphorus will form a pair.
Hence, Pair 1 has Mg and Sr, Pair 2 has Kr and Ne, Pair 3 has As and P.