x=3
Use the pythagorean theorem:
a^2 + b^2 = c^2
4^2 + x^2 = 5^2
16 + x^2 = 25
x^2 = 25-16
x^2 = 9
√x^2 = √9
x = 3
Answer:
group # = # valence electrons
group 2= 2 valence electrons
Explanation:
Mg is in group #2 and subsequently has 2 valence electrons (electrons on the outermost shell)
It's melting, so solid to liquid