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 Table: Main Group Element Charges

GOB Chemistry

3. Ionic Compounds

Periodic Table: Main Group Element Charges

Previous problemNext problem

3:35 minutes

Problem 112c

Textbook Question

Consider an ion with the symbol Y^3- formed from a representative element.
c. If Y is in Period 3, what is the element?

Verified step by step guidance

Identify the charge of the ion, which is 3⁻. This indicates that the element has gained 3 electrons to form the ion.

Determine the number of valence electrons in the neutral atom of the element. Since the ion has gained 3 electrons, the neutral atom must have had 5 valence electrons to reach a full octet (8 valence electrons).

Locate the group in the periodic table that corresponds to 5 valence electrons. Elements with 5 valence electrons are in Group 15 (or Group 5A in older notation).

Focus on Period 3 of the periodic table, as the problem specifies that the element is in Period 3. The element in Group 15 and Period 3 is phosphorus (P).

Conclude that the element Y is phosphorus (P), and the ion Y³⁻ corresponds to the phosphide ion (P³⁻).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Ion Formation

Ions are charged particles that form when atoms gain or lose electrons. A cation has a positive charge due to the loss of electrons, while an anion has a negative charge from gaining electrons. In this case, Y³⁻ indicates that the element has gained three electrons, resulting in a negative charge.

Periodic Table and Periods

The periodic table organizes elements based on their atomic number and properties. Each horizontal row is called a period, and elements in the same period share similar energy levels. Period 3 includes elements such as sodium, magnesium, and sulfur, which are crucial for identifying the element Y.

Representative Elements

Representative elements, also known as main group elements, are found in groups 1, 2, and 13-18 of the periodic table. They exhibit a wide range of chemical and physical properties and typically form predictable ions. Understanding that Y is a representative element helps narrow down the possibilities for its identity in Period 3.

Watch next

Master Periodic Table: Main Group Element Charges Concept 1 with a bite sized video explanation from Jules

Start learning