how many valence electrons? p sr al fr si ne se he
how many valence electrons? p sr al fr si ne se he
Answer
Explanation:
Step1: Recall valence - electron rules
Valence electrons are determined by the group number in the periodic table (for main - group elements).
Step2: Determine for P (Phosphorus)
P is in group 15. So it has 5 valence electrons.
Step3: Determine for Sr (Strontium)
Sr is in group 2. So it has 2 valence electrons.
Step4: Determine for Al (Aluminum)
Al is in group 13. So it has 3 valence electrons.
Step5: Determine for Fr (Francium)
Fr is in group 1. So it has 1 valence electron.
Step6: Determine for Si (Silicon)
Si is in group 14. So it has 4 valence electrons.
Step7: Determine for Ne (Neon)
Ne is a noble gas in group 18. It has 8 valence electrons.
Step8: Determine for Se (Selenium)
Se is in group 16. So it has 6 valence electrons.
Step9: Determine for He (Helium)
He is a noble gas. It has 2 valence electrons.
Answer:
P: 5, Sr: 2, Al: 3, Fr: 1, Si: 4, Ne: 8, Se: 6, He: 2