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2 years ago

La is element 57 on the periodic table a sample contains 2.82 * 10€25 power atoms of La calculate the amount of LA

Chemistry

1 answer:

vodka [1.7K]2 years ago

5 0

Answer:

$n=46.8molLa\\\\m=6.50x10^3gLa$

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:

$n=2.82x10^{25}atomsLa*\frac{1molLa}{6.022x10^{23}atomsLa}=46.8molLa\\\\m=46.8molLa*\frac{138.9gLa}{1molLa} =6.50x10^3gLa$

Regards!

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