Answer:
[tex]n=46.8molLa\\\\m=6.50x10^3gLa[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to calculate both moles and grams of lanthanum by using the Avogadro's number as a relationship of atoms to moles and its atomic mass as a relationship to moles to grams to obtain the following:
[tex]n=2.82x10^{25}atomsLa*\frac{1molLa}{6.022x10^{23}atomsLa}=46.8molLa\\\\m=46.8molLa*\frac{138.9gLa}{1molLa} =6.50x10^3gLa[/tex]
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