Textbook Question
Determine whether each of the following statements is true or false. c. The number of electrons in an atom equals the number of neutrons in the atom.
2. Atoms & Elements
Subatomic Particles
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
A Se ion has a mass number of 75 and a charge of -2. Determine the number of neutrons, protons, and electrons in this ion.
A
34 neutrons, 41 protons, 36 electrons
B
41 neutrons, 36 protons, 34 electrons
C
41 neutrons, 34 protons, 36 electrons
D
41 neutrons, 34 protons, 32 electrons
Verified step by step guidance1
Identify the atomic number of selenium (Se) from the periodic table, which is 34. This represents the number of protons in the atom.
Since the ion has a charge of -2, it has gained 2 extra electrons compared to the neutral atom. Therefore, calculate the number of electrons by adding 2 to the atomic number: 34 + 2 = 36 electrons.
The mass number of the ion is given as 75. The mass number is the sum of protons and neutrons in the nucleus. Use the formula: \( \text{Mass Number} = \text{Protons} + \text{Neutrons} \).
Substitute the known values into the formula to find the number of neutrons: \( 75 = 34 + \text{Neutrons} \). Solve for neutrons: \( \text{Neutrons} = 75 - 34 \).
Calculate the number of neutrons: \( \text{Neutrons} = 41 \). Therefore, the Se ion has 41 neutrons, 34 protons, and 36 electrons.
Related Videos
Related Practice
Subatomic Particles practice set
Problem sets built by lead tutorsExpert video explanations