Problem 21 - Chemistry: Principles and Reactions

Question

How many metals are in the following groups? (a) Group 1 (b) Group 13 (c) Group 17

Step-by-Step Solution

Answer

Answer: There are 6 metals in Group 1, 4 metals in Group 13, and no metals in Group 17.

Step 1: Group 1 - Alkali Metals

Group 1 elements are all metals called Alkali metals, which include Hydrogen, Lithium, Sodium, Potassium, Rubidium, Cesium, and Francium. However, Hydrogen is not a metal, so there are 6 metals in Group 1.

Step 2: Group 13 - Boron Group

Group 13 elements are called the Boron group which include Boron, Aluminum, Gallium, Indium, and Thallium. Boron is a metalloid, meaning it has properties of both metals and non-metals, while the remaining 4 elements in this group are all metals. Thus, there are 4 metals in Group 13.

Step 3: Group 17 - Halogens

Group 17 elements are called Halogens, which include Fluorine, Chlorine, Bromine, Iodine, and Astatine. All of these elements are non-metals, except Astatine which is considered a metalloid. Hence, there are no metals in Group 17. In conclusion, there are 6 metals in Group 1, 4 metals in Group 13, and no metals in Group 17.

Key Concepts

Alkali Metals

The alkali metals form Group 1 on the periodic table. This group consists of six metals: Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr). Despite being in the same column, Hydrogen is not classified as a metal. Alkali metals are known for their high reactivity, especially with water, forming alkaline solutions. They possess a single electron in their outermost shell, making them eager to lose that electron in chemical reactions. This makes them excellent conductors of electricity. You'll find them stored in oil to prevent unwanted reactions with air and moisture.

Boron Group

The Boron group encompasses Group 13 of the periodic table. In this group, the elements Boron (B), Aluminum (Al), Gallium (Ga), Indium (In), and Thallium (Tl) are present. Boron, unique among them, is a metalloid. It exhibits characteristics of both metals and non-metals. The remaining elements in this group are metals. These metals are known for being softer and possessing lower melting points compared to transition metals. They often see use in electronics, with Aluminum especially notable due to its abundance and versatility.

Halogens

Halogens form Group 17 in the periodic table, consisting of Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At). As non-metals, most halogens are reactive and naturally occur as compounds rather than in their free form. Notably, Astatine is considered a metalloid, straddling the line between metals and non-metals. These elements are known for their ability to form salts, hence the name 'halogen' which means 'salt former'. They typically exist as diatomic molecules (e.g., F₂, Cl₂) and play significant roles in both industrial and biological processes.

Metalloids

Metalloids, also known as semimetals, possess properties between those of metals and non-metals. They include elements like Boron (B), Silicon (Si), and Astatine (At), among others. These elements can conduct electricity better than non-metals but not as well as metals, which makes them useful in the semiconductor industry. They often show mixed chemical behavior, sometimes forming alloys with metals or sharing characteristics with non-metals. Their unique properties make them crucial in technology and materials engineering.

Chemical Elements Classification

The periodic table is a systematic arrangement of chemical elements classified into various groups based on similar properties. Major classifications include metals, non-metals, and metalloids. Metals are generally good conductors of heat and electricity, possess high density, and are typically malleable. Non-metals, on the other hand, are poor conductors and more likely to be brittle if solid. Metalloids exhibit intermediate properties. The classification helps in predicting and understanding the chemical behavior of elements, aiding in applications across different scientific and industrial fields.