Silver has an atomic number of 47.
a. Give the number of protons, neutrons, and electrons in a neutral atom of the most common isotope, Ag-107.
b. How do the numbers of protons, neutrons, and electrons in a neutral atom of Ag-109 compare with those of Ag-107?
The correct answer and explanation is :
a. Number of protons, neutrons, and electrons in a neutral atom of Ag-107:
- Protons: The atomic number of silver (Ag) is 47, which means every silver atom has 47 protons.
- Neutrons: The number of neutrons can be calculated by subtracting the atomic number from the atomic mass. For Ag-107, the atomic mass is approximately 107, so the number of neutrons is: [
\text{Neutrons} = \text{Atomic Mass} – \text{Atomic Number} = 107 – 47 = 60
] - Electrons: Since the atom is neutral, the number of electrons equals the number of protons, so there are 47 electrons in Ag-107.
Thus, in a neutral atom of Ag-107:
- Protons = 47
- Neutrons = 60
- Electrons = 47
b. Comparison with Ag-109:
For Ag-109, the number of protons remains the same because it is still silver (Ag) with an atomic number of 47. However, the atomic mass is 109, so we calculate the number of neutrons as follows:
[
\text{Neutrons} = \text{Atomic Mass} – \text{Atomic Number} = 109 – 47 = 62
]
Therefore, the number of protons in both Ag-107 and Ag-109 is the same, 47, because the atomic number is the same. The difference between these two isotopes lies in the number of neutrons:
- Ag-107 has 60 neutrons.
- Ag-109 has 62 neutrons.
The number of electrons in both isotopes will also be the same (47 electrons), assuming the atoms are neutral.
Thus, the main difference between Ag-107 and Ag-109 is the number of neutrons:
- Ag-107: 60 neutrons
- Ag-109: 62 neutrons
These differences in neutrons result in slightly different atomic masses for the two isotopes, but they are both silver atoms and exhibit almost identical chemical properties.
The image above provides a clear comparison between the two isotopes, Ag-107 and Ag-109, highlighting the differences in the number of neutrons.
- Ag-107 has 47 protons, 60 neutrons, and 47 electrons.
- Ag-109 has 47 protons, 62 neutrons, and 47 electrons.
The diagram visually represents the structure of these isotopes and helps illustrate how the number of neutrons changes between the two, while the number of protons and electrons remains the same for both.