Atom of Gold: Protons, Neutrons, and Electrons
How many protons, neutrons, and electrons are there in an uncharged atom of gold?
Choose the correct option:
A. 79 protons, 118 neutrons, 79 electrons
B. 118 protons, 79 neutrons, 118 electrons
C. 118 protons, 276 neutrons, 118 electrons
D. 79 protons, 34 neutrons, 79 electrons
Answer:
An uncharged atom of gold has 79 protons, 118 neutrons, and 79 electrons.
An uncharged atom of gold has an atomic number of 79 and an atomic mass of 197. This means that the atom has 79 protons, as the atomic number identifies the number of protons in the nucleus.
Since the atom is uncharged, it must have the same number of electrons as protons, which in this case is 79 electrons.
The atomic mass of the gold atom is the sum of protons and neutrons, approximately 197. By subtracting the number of protons (79) from the atomic mass (197), we find that the atom has 118 neutrons.
Therefore, the correct answer is (A): 79 protons, 118 neutrons, and 79 electrons in an uncharged atom of gold.