Question

What is the mass, in grams, of a sample of 6.98 × 1024 atoms of magnesium (Mg)? Show your work or explain the steps that you used to determine your answer.

Answer 1

Hello!

* First Step: to know Avogrado's Law

We know that by the Law of Avogrado, for each mole of substance we have 6.02*10²³ atoms, if:

** Second Step: to know the molar mass of the solute

The molar mass of of magnesium = 24.30 g/mol

*** Third step: make the ratio mass / mol with atoms

1 mol we have 6.02*10²³ atoms

1 mole of Mg we have 24.30 g

Then we have:

24.30 g ------------- 6.02*10²³ atoms

x ----------------------- 6.98*10^24 atoms

$\dfrac{24.30}{x} = \dfrac{6.02*10^{23}}{6.98*10^{24}}$

multiply cross

$6.02*10^{23}*x = 24.30*6.98*10^{24}$

$6.02*10^{23}\:x = 1.69614*10^{26}$

$x = \dfrac{1.69614*10^{26}}{6.02*10^{23}}$

$\boxed{\boxed{x \approx 281.75\:grams}}\end{array}}\qquad\checkmark$

I Hope this helps, greetings ... DexteR! =)