Question

explain electronic configuration for first 20 elements ​

Answer 1

Explanation:

Refer image for your answer

Answer 2

Explanation:

H - 1s¹

He - 1s²

Li - 1s² 2s¹

Be - 1s² 2s²

B - 1s² 2s² 2p¹

C - 1s² 2s² 2p²

N - 1s² 2s² 2p³

O - 1s²2s²2p⁴

F - 1s² 2s² 2p⁵

Ne - 1s² 2s² 2p⁶

Na - 1s² 2s² 2p⁶ 3s¹

Mg - 1s² 2s² 2p⁶ 3s²

Al - 1s² 2s² 2p⁶ 3s² 3p¹

Si - 1s² 2s² 2p⁶ 3s² 3p²

P - 1s² 2s² 2p⁶ 3s² 3p³

S - 1s² 2s² 2p⁶ 3s² 3p⁴

Cl - 1s² 2s² 2p⁶ 3s² 3p⁵

Ar - 1s² 2s² 2p⁶ 3s² 3p⁶

K - 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

Ca - 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²