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 :
Answer:
(a) Number of protons, neutrons, and electrons in Ag-107:
- Protons: 47 (equal to the atomic number of silver)
- Electrons: 47 (since it’s a neutral atom, the number of electrons equals the number of protons)
- Neutrons: 107 – 47 = 60 (mass number minus atomic number)
(b) Comparison between Ag-109 and Ag-107:
- Protons: Both Ag-107 and Ag-109 have 47 protons.
- Electrons: Both have 47 electrons (as they are neutral atoms).
- Neutrons: Ag-109 has 109 – 47 = 62 neutrons, which is two more neutrons than Ag-107.
Explanation:
Silver (Ag) is a chemical element with an atomic number of 47, meaning every silver atom has 47 protons in its nucleus. A neutral atom of silver must also have 47 electrons to balance the positive charge of the protons.
The mass number of an isotope represents the sum of protons and neutrons in the nucleus. The most common isotope, Ag-107, has a mass number of 107, so the number of neutrons is calculated by:
[
\text{Neutrons} = \text{Mass Number} – \text{Atomic Number} = 107 – 47 = 60
]
Similarly, for Ag-109, the isotope has a mass number of 109, meaning the neutron count is:
[
\text{Neutrons} = 109 – 47 = 62
]
The only difference between Ag-107 and Ag-109 is the number of neutrons in the nucleus. Ag-109 has two more neutrons than Ag-107. However, both isotopes have the same chemical properties because chemical behavior is determined by electrons, and both have 47 electrons.
Physically, the extra neutrons in Ag-109 make it slightly heavier than Ag-107. These isotopes can be distinguished using techniques like mass spectrometry. The different isotopes may also affect nuclear stability and reaction behavior in some cases, but for silver, both Ag-107 and Ag-109 are stable isotopes.