How can you efficiently determine the number of atoms in a sample of an element?
a. first determine the mass of the sample and then convert it to the number of atoms using the molar mass of the element.
b. first determine the mass of the sample and then convert it to the number of atoms using avogadro's number and the molar mass of the element.
c. use atomic microscope to determine avogadro's number, then determine the mass of the sample and convert it to the number of atoms.
d. use atomic microscope to count each atom.

b. First determine the mass of the sample and then convert it to the number of atoms using Avogadro's number and the molar mass of the element.

Explanation:

a. First determine the mass of the sample and then convert it to the number of atoms using the molar mass of the element.  FALSE. As the mass is in grams and molar mass is in g/mol. This result in the moles of each element, not its number of atoms.

b. First determine the mass of the sample and then convert it to the number of atoms using Avogadro's number and the molar mass of the element.  TRUE. Mass and molar mass will result in moles of element. These moles could be converted in number of atoms using Avogadro's number that is in # atoms per mole.

c.Use atomic microscope to determine Avogadro's number, then determine the mass of the sample and convert it to the number of atoms.  FALSE. An atomic microscope is not used to determine Avogadro's number.

d.Use atomic microscope to count each atom. FALSE. There is not possible to count every single atom in an element. There are more atoms in a drop of water than stars in the sky.

I hope it helps!

there all right good

explanation: