D. 8
You can predict it from it's name "Octet" means Eight. Atom must have that number of electron to have a stable structure!
Hope this helps!
Answer: I think the right answer is c
The number of grams of NaOH that are needed to make 500 ml of 2.5 M NaOH solution
calculate the number of moles =molarity x volume/1000
= 2.5 x 500/1000 = 1.25 moles
mass = moles x molar mass of NaOH
= 1.25 x40= 50 grams of NaOH
From the periodic chart the only element between F and Na is Neon. Neon has one more valence electron 8 than fluorine 7, and is one energy level shy of Na.<span>
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