Answer:
You also know about the mass of that sample, if you know the moles
(First option)
Explanation:
Moles = Mass / Molar mass
Moles . Molar mass = Mass
For example, I have 4 moles of H₂O
Molar mass H₂O = 18 g/m
4 m . 18 g/m = 72 g
If I have 4 moles of H₂O, I also have 72 grams of water too.
I think Arêtes is what you’re referring to
Answer:

Explanation:
Hello!
In this case, since isotopes of the same element have the same number of protons and electrons but different atomic mass, we can compute the number of neutrons by subtracting the number of protons to the atomic mass of the isotope; thus, for Ga-69 and Ga-71 (rounded up to whole numbers), we obtain:

Best regards!
Hey im happy to help!
Heat can float from one place to another, like all energy.Heat floats in solids by conduction, that happens because the molecules hit one another.Heat within the solid will flow from hot to cold.Heat will flow downward if its cold there.
Hope this helps, have a great rest of your day!