Physical Science Ch.5 Semester 2 Exam Review

Explanation
Group 18 on the periodic table refers to the noble gases. These elements have a full outer electron shell, which makes them stable and unreactive. Due to their stable electron configuration, noble gases do not easily form chemical bonds with other elements. This inertness is what gives them their name "noble" gases.

Explanation
The elements in groups 3-12 are called transitional metals because they are characterized by their ability to form stable ions with varying charges and exhibit transitional properties between the highly reactive alkali and alkaline earth metals and the less reactive metals in the p-block. These metals often have multiple oxidation states and are known for their high melting and boiling points, as well as their ability to form complex compounds. They are widely used in various industries due to their desirable properties such as conductivity, malleability, and catalytic activity.

Explanation
The s and p orbitals bond together. These orbitals have different shapes and orientations, with the s orbital being spherical and the p orbital having a dumbbell shape. When two atoms come close together, their s and p orbitals can overlap and form molecular orbitals, allowing for the formation of chemical bonds. The s and p orbitals can combine to form sigma (σ) bonds, which are strong and result in a stable molecule. Therefore, the s and p orbitals are the ones that primarily participate in bonding.

Explanation
The periodic table is organized into different groups or categories based on the properties of the elements. The four types mentioned in the answer are alkali metals, alkali-earth metals, transitional metals, and halogens. Alkali metals are highly reactive and typically found in group 1 of the periodic table. Alkali-earth metals are also reactive but less so than alkali metals and are found in group 2. Transitional metals are located in the middle of the periodic table and have a wide range of properties. Halogens are highly reactive nonmetals found in group 17. These four types represent different groups of elements with distinct characteristics.