Multiple Choice
Astatine has 85 protons. What is its atomic number?
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- 1. Intro to General Chemistry3h 48m
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2. Atoms & Elements
The Atom
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
The atomic number of oxygen is 8. What is the mass number of an oxygen atom with 7 neutrons?
A
15
B
7
C
16
D
8
Verified step by step guidance1
Recall that the atomic number (Z) represents the number of protons in an atom. For oxygen, Z = 8, so it has 8 protons.
Understand that the mass number (A) is the total number of protons and neutrons in the nucleus of an atom.
Use the formula for mass number: \(A = Z + N\), where \(N\) is the number of neutrons.
Substitute the given values into the formula: \(A = 8 + 7\).
Add the numbers to find the mass number, which represents the total nucleons in this oxygen atom.
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