How many Mg^(2+)Mg2+ ions are present in 3.00 moles of MgCl_2MgCl2?

1 Answer
Aug 6, 2018

1.81" x "10^24 Mg^(2+) "ions" 1.81 x 1024Mg2+ions

Explanation:

Step 1:
From the formula MgCl_2MgCl2, we know that it's made from 1 Mg^(2+)Mg2+ and 2 Cl^-Cl ions

  • In 1 mol of MgCl_2MgCl2, there's 1 mol of Mg^(2+)Mg2+

We can use this relationship to calculate the moles of Mg^(2+) "ions"Mg2+ions from the given 3.00 moles of MgCl_2MgCl2.

Step 2:
Once we find the moles of Mg^(2+)Mg2+, we can find the number of Mg^(2+) "ions"Mg2+ions using Avogadro's number.

  • 1 mol Mg^(2+)Mg2+ has 6.0226.022 x 10^231023 Mg^(2+) "ions"Mg2+ions

Combining the 2 steps calculations:
Mg^(2+)"ions"="3.00 mols " MgCl_2 xx ("1 mol " Mg^(2+))/("1 mol " MgCl_2)xx(6.022 " x " 10^23 Mg^(2+) ions)/("1 mol " Mg^(2+))=1.81" x "10^24 Mg^(2+) "ions" Mg2+ions=3.00 mols MgCl2×1 mol Mg2+1 mol MgCl2×6.022 x 1023Mg2+ions1 mol Mg2+=1.81 x 1024Mg2+ions