Multiple Choice
How many protons are present in an atom of cobalt (Co)?
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Table of contents
- 1. Intro to General Chemistry3h 48m
- Classification of Matter18m
- Physical & Chemical Changes19m
- Chemical Properties7m
- Physical Properties5m
- Intensive vs. Extensive Properties13m
- Temperature12m
- Scientific Notation13m
- SI Units7m
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- Significant Figures9m
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- Conversion Factors16m
- Dimensional Analysis17m
- Density12m
- Density of Geometric Objects19m
- Density of Non-Geometric Objects7m
- 2. Atoms & Elements4h 16m
- The Atom9m
- Subatomic Particles15m
- Isotopes17m
- Ions27m
- Atomic Mass28m
- Periodic Table: Classifications11m
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- 22. Organic Chemistry5h 7m
- Introduction to Organic Chemistry8m
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- Skeletal Formula6m
- Spatial Orientation of Bonds3m
- Intro to Hydrocarbons16m
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- Chirality15m
- Functional Groups in Chemistry11m
- Naming Alkanes4m
- The Alkyl Groups9m
- Naming Alkanes with Substituents13m
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- Naming Alcohols11m
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- Alkane Reactions7m
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- 23. Chemistry of the Nonmetals2h 39m
- Main Group Elements: Bonding Types4m
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- Main Group Elements: Density11m
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- The Electron Configuration Review16m
- Periodic Table Charges Review20m
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- Production of Hydrogen8m
- Group 1A and 2A Reactions7m
- Boron Family Reactions7m
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- Oxides, Peroxides, and Superoxides12m
- Oxide Reactions4m
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- Noble Gas Compounds3m
- 24. Transition Metals and Coordination Compounds3h 16m
- Atomic Radius & Density of Transition Metals11m
- Electron Configurations of Transition Metals7m
- Electron Configurations of Transition Metals: Exceptions11m
- Paramagnetism and Diamagnetism10m
- Ligands10m
- Complex Ions5m
- Coordination Complexes7m
- Classification of Ligands11m
- Coordination Numbers & Geometry9m
- Naming Coordination Compounds22m
- Writing Formulas of Coordination Compounds8m
- Isomerism in Coordination Complexes14m
- Orientations of D Orbitals4m
- Intro to Crystal Field Theory10m
- Crystal Field Theory: Octahedral Complexes5m
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- Crystal Field Theory: Square Planar Complexes4m
- 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
How many electrons can the second energy level of an atom hold?
A
2
B
18
C
6
D
8
Verified step by step guidance1
Recall that the number of electrons an energy level can hold is determined by the formula \$2n^2\(, where \)n$ is the principal quantum number (energy level).
Identify the second energy level, so \(n = 2\).
Substitute \(n = 2\) into the formula: \$2 \times (2)^2$.
Calculate the value inside the parentheses first: \((2)^2 = 4\).
Multiply by 2 to find the maximum number of electrons: \$2 \times 4 = 8$ electrons.
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