Multiple Choice
How is the average atomic mass of an element calculated?
Table of contents
- 1. Intro to General Chemistry3h 48m
- Classification of Matter18m
- Physical & Chemical Changes19m
- Chemical Properties7m
- Physical Properties5m
- Intensive vs. Extensive Properties13m
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- Scientific Notation13m
- SI Units7m
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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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- 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
- Paramagnetism and Diamagnetism8m
- The Electron Configuration: Quantum Numbers16m
- Valence Electrons of Elements12m
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- 18. Aqueous Equilibrium4h 47m
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- Solubility Product Constant: Ksp17m
- Ksp: Common Ion Effect18m
- Precipitation: Ksp vs Q12m
- Selective Precipitation9m
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- 19. Chemical Thermodynamics1h 50m
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- Intro to Radioactivity10m
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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
- Naming Alkynes9m
- Naming Ketones5m
- Naming Aldehydes5m
- Naming Carboxylic Acids4m
- Naming Esters8m
- Naming Ethers5m
- Naming Amines5m
- Naming Benzene7m
- Alkane Reactions7m
- Intro to Addition Reactions4m
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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
Atomic Mass
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
What is the atomic number of potassium?
A
18
B
20
C
19
D
21
Verified step by step guidance1
Understand that the atomic number of an element is the number of protons in the nucleus of an atom of that element. It is a unique identifier for each element.
Recall that the atomic number is found on the periodic table, usually located above the element symbol.
Locate potassium on the periodic table. Potassium is represented by the symbol 'K'.
Identify the atomic number associated with potassium on the periodic table. This number is typically found above the element symbol 'K'.
Recognize that the atomic number of potassium is 19, which indicates it has 19 protons in its nucleus.
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