Answer:
[tex]4.08x10^{25} molecules[/tex]
Explanation:
Hello there!
In this case, since the understanding of the mole-molecules relationships is analyzed via the Avogadro's number:
[tex]1mol=6.022x10^{23}molecules[/tex]
Next, we can solve the following setup by starting with the 67.8 moles of helium and obtaining the required molecules as follows:
[tex]67.8mol*\frac{6.022x10^{23}molecules}{1mol}\\\\=4.08x10^{25} molecules[/tex]
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