WRITE THE ELECTRONIC CONFIGURATION OF THE FIRST 20 ELEMENT ON THE PERIODIC TABLE.

Here are the electronic configurations for the first 20 elements:

• 1. Hydrogen (H) ($Z=1$): $1s^1$
• 2. Helium (He) ($Z=2$): $1s^2$
• 3. Lithium (Li) ($Z=3$): $1s^2 2s^1$
• 4. Beryllium (Be) ($Z=4$): $1s^2 2s^2$
• 5. Boron (B) ($Z=5$): $1s^2 2s^2 2p^1$
• 6. Carbon (C) ($Z=6$): $1s^2 2s^2 2p^2$
• 7. Nitrogen (N) ($Z=7$): $1s^2 2s^2 2p^3$
• 8. Oxygen (O) ($Z=8$): $1s^2 2s^2 2p^4$
• 9. Fluorine (F) ($Z=9$): $1s^2 2s^2 2p^5$
• 10. Neon (Ne) ($Z=10$): $1s^2 2s^2 2p^6$
• 11. Sodium (Na) ($Z=11$): $1s^2 2s^2 2p^6 3s^1$
• 12. Magnesium (Mg) ($Z=12$): $1s^2 2s^2 2p^6 3s^2$
• 13. Aluminum (Al) ($Z=13$): $1s^2 2s^2 2p^6 3s^2 3p^1$
• 14. Silicon (Si) ($Z=14$): $1s^2 2s^2 2p^6 3s^2 3p^2$
• 15. Phosphorus (P) ($Z=15$): $1s^2 2s^2 2p^6 3s^2 3p^3$
• 16. Sulfur (S) ($Z=16$): $1s^2 2s^2 2p^6 3s^2 3p^4$
• 17. Chlorine (Cl) ($Z=17$): $1s^2 2s^2 2p^6 3s^2 3p^5$
• 18. Argon (Ar) ($Z=18$): $1s^2 2s^2 2p^6 3s^2 3p^6$
• 19. Potassium (K) ($Z=19$): $1s^2 2s^2 2p^6 3s^2 3p^6 4s^1$
• 20. Calcium (Ca) ($Z=20$): $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2$