How many protons(p), neutrons(n), and electrons(e) does the following ion have?   P3- Group of answer choices 31p, 15n, 15e 15p, 16n, 18e 15p, 16n, 12e 15p, 16n, 15e How many protons(p), neutrons(n), and electrons(e) does the following ion have?   P3- Group of answer choices 31p, 15n, 15e 15p, 16n, 18e 15p, 16n, 12e 15p, 16n, 15e
The Correct Answer and Explanation is :
The correct answer is:
15p, 16n, 18e
Explanation:
- Understanding the Atomic Structure of Phosphorus (P)
Phosphorus (P) is an element with an atomic number of 15, which means it has 15 protons (p) in its nucleus. The number of protons determines the identity of the element. - Determining the Number of Neutrons (n)
The most common isotope of phosphorus has a mass number of 31 (given by the periodic table). The mass number is the sum of protons and neutrons:
[
\text{Neutrons} = \text{Mass number} – \text{Protons} = 31 – 15 = 16
]
So, phosphorus has 16 neutrons in its nucleus. - Determining the Number of Electrons (e) in P³⁻ Ion
- A neutral phosphorus atom has 15 electrons (equal to its protons).
- The P³⁻ ion means that the phosphorus atom has gained three additional electrons, making the total electron count:
[
15 + 3 = 18
] - This extra negative charge results from an excess of three electrons compared to the neutral state.
- Final Answer Breakdown:
- Protons (p): 15 (always remains the same for phosphorus).
- Neutrons (n): 16 (based on the isotope with mass number 31).
- Electrons (e): 18 (because it gained three extra electrons).
Why the Other Answers Are Incorrect:
- 31p, 15n, 15e: Wrong because mass number 31 includes both protons and neutrons, not just protons.
- 15p, 16n, 12e: Wrong because a neutral phosphorus atom has 15 electrons, so losing 3 electrons would result in P³⁺, not P³⁻.
- 15p, 16n, 15e: Wrong because it represents a neutral phosphorus atom, not an ion.
Thus, the correct answer is 15p, 16n, 18e.