The mineral that is the hardest known substance in nature is a diamond.
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Write the symbols for the cation and the anion: Mg and Cl. Determine the charge on the cation and anion. If the cation has a Roman numeral after it, that is the charge on that cation. Cations receive Roman numerals when they can take more than one ionicform.
periodical table and write caculatoin numbers
Answer:
5 000 000 (5 million atoms)
Explanation:
Let us assume that a vanadium atom has a spherical shape.
diameter of a sphere = 2 x radius of the sphere
Thus,
Radius of a vanadium atom = 130 pm
= 130 x
m
The diameter of a vanadium atom = 2 x radius
= 2 x 130 x
= 260 x
m
Given a distance of 1.30 mm = 1.30 x
m,
The number of vanadium atoms required to span the distance = 
= 5000000
Therefore, the number of vanadium atom that would span a distance of 1.30 mm is 5 million.
Y=15 x=60
•1/3 •1/3
y=5 x=45