Multiple Choice
How many protons and electrons are present in a neutral atom of strontium (Sr)?
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Table of contents
- 1. Intro to General Chemistry3h 48m
- Classification of Matter18m
- Physical & Chemical Changes19m
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- 2. Atoms & Elements4h 16m
- The Atom9m
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- 24. Transition Metals and Coordination Compounds3h 16m
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- Complex Ions5m
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- Crystal Field Theory Summary8m
- Magnetic Properties of Complex Ions9m
- Strong-Field vs Weak-Field Ligands6m
- Magnetic Properties of Complex Ions: Octahedral Complexes11m
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
An atom has an atomic number of 15 and a mass number of 31. How many protons are present in this atom?
A
16
B
46
C
15
D
31
Verified step by step guidance1
Recall that the atomic number of an atom represents the number of protons in its nucleus.
Identify the atomic number given in the problem, which is 15.
Understand that the mass number is the sum of protons and neutrons, but it does not affect the number of protons directly.
Since the atomic number is 15, the atom has 15 protons.
Therefore, the number of protons in the atom is equal to the atomic number, which is 15.
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