Multiple Choice
An atom of calcium contains 20 protons. How many electrons does it have in its neutral state?
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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
- Metric Prefixes24m
- Significant Figures9m
- Significant Figures: Precision in Measurements8m
- Significant Figures: In Calculations14m
- 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
- Periodic Table: Group Names8m
- Periodic Table: Representative Elements & Transition Metals7m
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- Functional Groups in Chemistry11m
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- 10. Periodic Properties of the Elements3h 9m
- The Electron Configuration22m
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- The Electron Configurations: Exceptions13m
- The Electron Configuration: Ions12m
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- The Electron Configuration: Quantum Numbers16m
- Valence Electrons of Elements12m
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- 15. Chemical Kinetics2h 53m
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- 19. Chemical Thermodynamics1h 50m
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- Intro to Radioactivity10m
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- Band of Stability: Alpha Decay & Nuclear Fission10m
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- Band of Stability: Overview14m
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- Mass Defect18m
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- 22. Organic Chemistry5h 7m
- Introduction to Organic Chemistry8m
- Structural Formula8m
- Condensed Formula10m
- Skeletal Formula6m
- Spatial Orientation of Bonds3m
- Intro to Hydrocarbons16m
- Isomers11m
- Chirality15m
- Functional Groups in Chemistry11m
- Naming Alkanes4m
- The Alkyl Groups9m
- Naming Alkanes with Substituents13m
- Naming Cyclic Alkanes6m
- Naming Other Substituents8m
- Naming Alcohols11m
- Naming Alkenes11m
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- Naming Ketones5m
- Naming Aldehydes5m
- Naming Carboxylic Acids4m
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- Naming Benzene7m
- Alkane Reactions7m
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- Benzene Reactions10m
- 23. Chemistry of the Nonmetals2h 39m
- Main Group Elements: Bonding Types4m
- Main Group Elements: Boiling & Melting Points7m
- Main Group Elements: Density11m
- Main Group Elements: Periodic Trends7m
- The Electron Configuration Review16m
- Periodic Table Charges Review20m
- Hydrogen Isotopes4m
- Hydrogen Compounds11m
- Production of Hydrogen8m
- Group 1A and 2A Reactions7m
- Boron Family Reactions7m
- Boron Family: Borane7m
- Borane Reactions7m
- Nitrogen Family Reactions12m
- Oxides, Peroxides, and Superoxides12m
- Oxide Reactions4m
- Peroxide and Superoxide Reactions6m
- 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
- Crystal Field Theory: Tetrahedral Complexes4m
- 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 protons are present in an atom of oxygen?
A
16
B
6
C
12
D
8
Verified step by step guidance1
Identify the element in question, which is oxygen in this case.
Recall that the number of protons in an atom is equal to the atomic number of the element.
Look up the atomic number of oxygen on the periodic table, which is 8.
Understand that the atomic number (8) represents the number of protons in the nucleus of an oxygen atom.
Conclude that an oxygen atom contains 8 protons.
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