b. How many valence electrons do chlorine, bromine, and iodine have?

Verified step by step guidance

1. Step 1: Understand that valence electrons are the electrons in the outermost shell of an atom. They are the electrons that are involved in chemical reactions and bonding.
2. Step 2: Recall that chlorine (Cl), bromine (Br), and iodine (I) are all in Group 17 (also known as the Halogens) on the periodic table.
3. Step 3: Recognize that all elements in Group 17 have 7 valence electrons. This is because the outermost shell of these elements (the p orbital) has 5 electrons, and there are 2 additional electrons in the s orbital, making a total of 7 valence electrons.
4. Step 4: Therefore, chlorine, bromine, and iodine each have 7 valence electrons.

Key Concepts

Valence Electrons

Valence electrons are the outermost electrons of an atom and are crucial for determining how an element interacts chemically with other elements. They are involved in the formation of chemical bonds and influence the reactivity of the element. The number of valence electrons can often be determined by an element's position in the periodic table.

Group 17 Elements

Chlorine, bromine, and iodine belong to Group 17 of the periodic table, also known as the halogens. These elements are characterized by having seven valence electrons, which makes them highly reactive, particularly with alkali and alkaline earth metals. Their reactivity is due to their tendency to gain one additional electron to achieve a stable octet configuration.

Periodic Table Trends

The periodic table exhibits trends in the properties of elements, including the number of valence electrons. As you move down a group, such as Group 17, the number of electron shells increases, but the number of valence electrons remains the same. Understanding these trends helps predict the behavior of elements in chemical reactions and their bonding characteristics.