Question

Without referring to tables or figures in the text other than the periodic table, indicate which of the following atoms, \(\mathrm{Bi}, \mathrm{S}, \mathrm{Ba}, \mathrm{As},\) or \(\mathrm{Mg},\) has the intermediate value when they are arranged in order of increasing electronegativity.

Short answer

The atom with an intermediate electronegativity value when Bi, S, Ba, As, and Mg are arranged in order of increasing electronegativity is As.

Step-by-step solution

Identify the Positions on the Periodic Table

The first step is to identify where the given atoms, Bi, S, Ba, As, and Mg, are located on the periodic table:

Identify the Electronegativity Trends

The next step is to apply the understanding of the trends in electronegativity across the periodic table. Electronegativity tends to increase as moving from left to right across a period and decrease as moving down a group. Remember that the farthest to the left and down, the atom with the lowest electronegativity, and the farthest to the right and up, the atom with the highest electronegativity.

Arrange in Order of Electronegativity

Now arrange all the atoms in order of increasing electronegativity based on their positions in the periodic table. From left to right, and bottom to top:

Identify Atom with Intermediate Electronegativity

Finally, the atom having an intermediate value of electronegativity is the one in the middle of this arranged list.

Key concepts

Periodic Table

The periodic table is a powerful tool in chemistry, visually organizing the chemical elements based on their atomic structure and properties. This tabular arrangement lists elements in rows by increasing atomic number, meaning by the number of protons in their atomic nuclei. The vertical columns of the table are known as groups, and elements within the same group have similar chemical properties.
The structure of the periodic table helps predict characteristics of unknown elements and their compounds. It includes important trends such as atomic radius, ionization energy, and electronegativity, which change predictably across the table. In the context of electronegativity, understanding the table's layout allows us to predict how likely an atom is to attract electrons in a chemical bond.
To use the periodic table effectively, one should know the general location of elements. For example, metals are typically found on the left side, while non-metals are on the right. The group number can be used to determine shared properties among elements, making it easier to understand complex properties like electronegativity.

Electronegativity Trends

Electronegativity is a measure of how strongly an atom can attract and hold onto electrons when forming a chemical bond. Some atoms are more electronegative than others, meaning they have a stronger pull on electrons.
The periodic table reveals trends in electronegativity. As we move from left to right across a period, electronegativity generally increases. This happens because the atoms have more protons in the nucleus, pulling the electron cloud more tightly. Additionally, moving from top to bottom in a group usually leads to a decrease in electronegativity. The outer electrons are further from the nucleus, facing less effective nuclear charge.
Consider sulfur (S) and barium (Ba) in the periodic table. Sulfur is more electronegative because it is to the right of barium in the same period, reflecting an increased ability to attract electrons. Not all elements fit perfectly into this trend due to unique electronic configurations, but this rule of thumb provides a solid basis for understanding chemical interactions.

Chemical Elements

Chemical elements are pure substances consisting of one type of atom, each defined by its number of protons, known as the atomic number. The periodic table lists all known elements, from simple hydrogen with a single proton to more complex large atoms like uranium. Each element possesses unique properties that distinguish it from others.

• Metals: These are typically shiny, malleable, and good conductors of electricity and heat. For example, magnesium (Mg) is a metal often used in lightweight alloys.
• Non-metals: These elements tend to be poor conductors and have more varied properties. Sulfur (S), for example, is a non-metal important in many industrial processes.
• Metalloids: These have properties of both metals and non-metals, such as arsenic (As), often found in semiconductors.

Understanding these classifications helps in predicting an element's chemical reactivity and its role in compounds. Additionally, knowing an element's position on the periodic table gives insight into its properties like electronegativity.