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

6. Chemical Reactions & Quantities

Mole Concept

GOB Chemistry

6. Chemical Reactions & Quantities

Mole Concept

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Multiple Choice

A cylindrical copper wire is used for the fences around a house. The copper wire has a diameter of 0.0750 in. How many copper atoms are found in 5.160 cm piece? The density of copper is 8.96 g/cm³. (V = π • r² • h)

2.01 x 10²² Cu atoms

6.36 x 10²¹ Cu atoms

9.91 x 10²¹ Cu atoms

1.25 x 10²² Cu atoms

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Verified step by step guidance

Convert the diameter of the copper wire from inches to centimeters. Use the conversion factor: 1 inch = 2.54 cm.

Calculate the radius of the wire in centimeters by dividing the diameter by 2.

Use the formula for the volume of a cylinder, V = π • r^2 • h, to calculate the volume of the copper wire. Here, r is the radius in cm and h is the length of the wire in cm.

Calculate the mass of the copper wire using the density formula: mass = density × volume. Use the given density of copper, 8.96 g/cm³.

Determine the number of copper atoms by dividing the mass of the copper wire by the molar mass of copper (approximately 63.55 g/mol) to find the number of moles, and then multiply by Avogadro's number (6.022 x 10^23 atoms/mol) to find the total number of atoms.