Answer:
Cs
Explanation:
Number of atoms is directly proportional to number of moles, which is indirectly proportional to the molar mass.
Since the molar mass of Cesium is the greatest, it has the fewest number of atoms in a 10g sample.
The number of atoms contained by the given mass is obtained from Avogadro's number. The fewest atoms are contained in 10.0 g Ar.
The number of atoms in 10.0 g Na = 10g/23 g/mol * 6.02 * 10^23 = 2.6 * 10^23 atoms
The number of atoms in 10.0 g Li = 10g/7 g/mol * 6.02 * 10^23 = 8.6 * 10^23 atoms
The number of atoms in 10.0 g Ar = 10g/40 g/mol * 6.02 * 10^23 = 1.5 * 10^23 atoms
The number of atoms in 10.0 g Kr = 10 g/84g/mol * 6.02 * 10^23 = 7.2 * 10^23 atoms
The number of atoms in 10.0 g Cs = 10 g/ 133 g/mol * 6.02 * 10^23 = 4.5 * 10^23 atoms
Hence, 10.0 g Ar has the fewest atoms.
Learn more: https://brainly.com/question/1445383
