Question

Observe the given table and answer the following question :
· Elements
А
B
C
D
Atomic number
11
2
7
19
Identify the two elements that belong to the same period and the two elements
that belong to the same group. Give reason for your conclusion.​

Answer 1

Answer: a. Sodium

B. Helium

C.Nitrogen

D. Potassium

Explanation: