Table of contents

1. Matter and Measurements4h 31m
2. Atoms and the Periodic Table5h 23m
3. Ionic Compounds2h 18m
4. Molecular Compounds2h 18m
5. Classification & Balancing of Chemical Reactions3h 17m
6. Chemical Reactions & Quantities2h 27m
7. Energy, Rate and Equilibrium3h 46m
8. Gases, Liquids and Solids3h 25m
9. Solutions4h 10m
10. Acids and Bases3h 29m
11. Nuclear Chemistry56m
BONUS: Lab Techniques and Procedures1h 38m
BONUS: Mathematical Operations and Functions47m
12. Introduction to Organic Chemistry1h 34m
13. Alkenes, Alkynes, and Aromatic Compounds2h 12m
14. Compounds with Oxygen or Sulfur1h 6m
15. Aldehydes and Ketones1h 1m
16. Carboxylic Acids and Their Derivatives1h 11m
17. Amines39m
18. Amino Acids and Proteins1h 51m
19. Enzymes1h 37m
20. Carbohydrates1h 41m
21. The Generation of Biochemical Energy2h 8m
22. Carbohydrate Metabolism2h 22m
23. Lipids2h 26m
24. Lipid Metabolism1h 45m
25. Protein and Amino Acid Metabolism1h 37m
26. Nucleic Acids and Protein Synthesis2h 54m

3. Ionic Compounds

Periodic Trend: Ranking Ionic Radii

GOB Chemistry

3. Ionic Compounds

Periodic Trend: Ranking Ionic Radii

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Multiple Choice

Arrange the following atoms and/or ions in the order of increasing size:Br^–, Kr, Rb⁺, Sr²⁺.

Kr < Br^- < Sr²⁺ < Rb⁺

Kr < Sr²⁺ < Rb⁺ < Br^-

Sr²⁺ < Rb⁺ < Kr < Br^-

Rb⁺ < Sr²⁺ < Kr < Br^-

Br^- < Kr < Rb⁺ < Sr²⁺

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Verified step by step guidance

Identify the number of protons and electrons for each species: Br⁻, Kr, Rb⁺, and Sr²⁺. This will help determine their effective nuclear charge and electron configuration.

Understand that ions with the same number of electrons (isoelectronic species) will have different sizes based on their nuclear charge. The more protons, the smaller the ion, because the electrons are pulled closer to the nucleus.

Compare the electron configurations: Br⁻ has gained an electron, Kr is a noble gas with a full outer shell, Rb⁺ has lost an electron, and Sr²⁺ has lost two electrons. This affects their size.

Consider the effective nuclear charge: Br⁻ has the least nuclear charge for its electron count, making it larger. Sr²⁺ has the most nuclear charge for its electron count, making it smaller.

Arrange the species in order of increasing size based on the above analysis: Sr²⁺ < Rb⁺ < Kr < Br⁻.