Which of the following samples contains the greatest number of atoms?

a. 9 mole of CO2 b. 10 moles of Xe

c. 11 moles of N2O d. 12 moles of CO

C. 11 moles of N2O

Explanation:

A. CO2 exists as a molecular compound. The number of atoms present = 1 atom of Carbon and 2 atoms oxygen = 3 atoms * 9 = 18 atoms

B. Xe exists as an atom. Number of atoms present = 10 * 1 atom = 10 atoms

C. N20 contains 3 atoms; 2 atoms of Nitrogen and 1 atom of oxygen.

Number of atoms present = 3 * 11 = 33 atoms

D. CO contains 2 atoms, 1 each of carbon and oxygen.

Number of atoms present = 12 * 2 = 24 atoms