Question

An element with atomic number 20 is placed in which period of the periodic table ?

• A. 4
• B. 3
• C. 2
• D. 1

Answer 1

Answer: (A)

4

Answer 2

Z = 20

₂₀Ca = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

Period = 4^th