The atomic number of an atom represents the number of protons in its nucleus. Since the charge of the nucleus is given as 2.24 x 10^-18, we can determine the atomic number by dividing this charge by the elementary charge (1.602 x 10^-19 coulombs), which represents the charge of a single proton.
Atomic number = (Charge of nucleus) / (Elementary charge)
Atomic number = (2.24 x 10^-18 C) / (1.602 x 10^-19 C)
Calculating this expression gives:
Atomic number ≈ 14
Therefore, the atomic number of this atom is approximately 14.