General Chemistry
The periodic table consists of various types of elements, organized into rows called periods and columns called groups. Elements in the same group have the same number of valence electrons, granting them similar properties. Group one consists of the alkali metals, which are highly reactive elements often found in salts. Group two is made up of the alkaline earth metals, also reactive but less so than alkali metals. Groups three through twelve house the transition metals; these elements are typically shiny and conduct electricity well, including gold, silver, iron, and platinum.
Groups 13 through 18 consist of a diverse range of elements, including post-transition metals, metalloids, nonmetals, halogens, and noble gases. Metalloids have characteristics of both metals and nonmetals, while nonmetals are poor conductors. Halogens are fairly reactive and form salts and diatomic molecules. Noble gases are unique, being present as single atoms in nature, making them very unreactive. Lastly, the periodic table includes the lanthanides and actinides, which are generally reactive elements, with most actinides being radioactive.
Lesson Outline
<ul> <li>Periodic Table</li> <ul> <li>Periods (rows)</li> <li>Groups (columns)</li> <ul> <li>Group 1: Alkali Metals</li> <li>Group 2: Alkaline Earth Metals</li> <li>Groups 3-12: Transition Metals</li> <li>Post-transition Metals</li> <li>Metalloids</li> <li>Nonmetals</li> <ul> <li>Hydrogen</li> <li>Other Nonmetals (carbon, oxygen, etc.)</li> </ul> <li>Group 17: Halogens</li> <li>Group 18: Noble Gases</li> </ul> </ul> <li>Lanthanides (elements 57-71)</li> <li>Actinides (elements 89-103)</li> <ul> <li>Lathanides and actinides have electrons in incomplete F orbitals (4f and 5f, respectively)</li> <li>Reactivity and radioactivity</li> </ul> </ul>
Don't stop here!
Get access to 34 more General Chemistry lessons & 8 more full MCAT courses with one subscription!
FAQs
The periodic table is organized into several categories based on the properties of the elements. The main types of elements are alkali metals, alkaline earth metals, transition metals, post-transition metals, metalloids, nonmetals, halogens, and noble gases. Each category of elements is grouped together based on their similar behavioral patterns, chemical properties, and electron configurations.
Alkali metals and alkaline earth metals both belong to the group of metals known as s-block elements. Alkali metals are located in Group 1 of the periodic table and have one electron in their outermost energy level. They are highly reactive, soft metals that readily lose their outermost electron to form a +1 ion. Alkaline earth metals, on the other hand, are found in Group 2 of the periodic table and have two electrons in their outermost energy level. They are less reactive than alkali metals but still readily lose their two outer electrons to form a +2 ion.
Transition metals are found in Groups 3 to 12 on the periodic table and are characterized by their ability to form a wide range of positive ions. They typically have a variable oxidation state, high melting points, and they often form colorful compounds. Post-transition metals are found to the right of the transition metals in Groups 13 to 16. They are also metallic elements, but they are generally less reactive than transition metals and have a lower melting point. The distinction between transition metals and post-transition metals is not always clear, and some elements exhibit characteristics of both groups.
Metalloids are a unique group of elements that have properties of both metals and nonmetals. They are found along a diagonal line between Groups 13 and 16, running from boron (B) to astatine (At) on the periodic table. Metalloids are characterized by their intermediate electrical conductivity, which can be modified and controlled under various conditions. They tend to form amphoteric oxides that can act as both acidic and basic species. Metalloids are often used in the semiconductor industry due to their unique electronic properties.
Halogens are found in Group 17 of the periodic table and are highly reactive nonmetals. They have a strong tendency to gain one electron to achieve a stable, full outer electron shell. Halogens are known for forming salts when reacted with metals and have various uses, such as in disinfectants and as components of some medicines. Noble gases, on the other hand, are located in Group 18 of the periodic table and are highly unreactive due to their full outer electron shells. These gases are inert and do not typically form compounds with other elements, although some compounds known as noble gas compounds have been synthesized in laboratory conditions. Noble gases have various applications, including as components in lighting and medical equipment.
MCAT® is a registered trademark of the Association of American Medical Colleges. The United States Medical Licensing Examination (USMLE®) is a joint program of the Federation of State Medical Boards (FSMB®) and National Board of Medical Examiners (NBME®). NAPLEX® is a registered trademark of the National Association of Boards of Pharmacy. PANCE© is a registered trademark of the National Commission on Certification of Physician Assistants. NCLEX® is a registered trademark and service mark of the National Council of State Boards of Nursing, Inc. None of the trademark holders are endorsed by nor affiliated with Sketchy or this website.
