Question

The atomic mass of the element neon (Ne) is 20.180 amu. Which measurement is correct?

a. 1 mole Ne = 20.180 grams = 1.215 x 10^25 atoms
b. 1 mole Ne = 20.180 moles = 6.022 x 10^23 atoms
c. 1 mole Ne = 20.180 grams = 6.022 x 10^23 atoms
d. 1 mole Ne = 20.180 moles = 1.215 x 10^25 atoms

Answer 1

The correct answer is:

c. 1 mole Ne = 20.180 grams = 6.022 x 10^23 atoms

The atomic mass of neon (Ne) is given as 20.180 amu, which means that one mole of neon atoms has a mass of 20.180 grams. This is known as the molar mass of neon.

Avogadro's number, 6.022 x 10^23, represents the number of atoms or molecules in one mole of a substance. Therefore, one mole of neon atoms contains 6.022 x 10^23 atoms.

Option (a) is incorrect because it gives the number of atoms as 1.215 x 10^25, which is more than 2 times Avogadro's number and is not a possible value.

Option (b) is incorrect because it gives the molar mass of neon as 20.180 moles, which is not a valid unit for molar mass.

Option (d) is incorrect because it combines the incorrect values from options (a) and (b).