2025 Chemistry Quarterly Exam 1 Full Practice Test

Group 2 of the periodic table is known as the alkaline earth metals. These elements are characterized by having two valence electrons in their outermost electron shell. This electronic configuration plays a crucial role in their chemical properties, such as their reactivity and the types of compounds they form.

Alkaline earth metals include elements such as beryllium, magnesium, calcium, strontium, barium, and radium. The presence of two valence electrons makes them more reactive than the noble gases, which have a complete valence shell and are largely unreactive. In contrast, alkaline earth metals readily lose their two valence electrons to form cations with a charge of +2, allowing them to participate in various chemical reactions.

The other groups mentioned in the choices do not share this same characteristic of having two valence electrons. The halogens, located in Group 17, typically have seven valence electrons and are known for their high reactivity with metals to form salts. Noble gases, in Group 18, possess a full valence shell, making them stable and largely nonreactive. Transition metals, found in Groups 3-12, have varying numbers of valence electrons due to the electron configurations that involve d-or