Question

Write the simple Lewis structure for each of the following atoms. a. I \((Z=53)\) b. \(\mathrm{Al}(Z=13)\) c. Xe \((Z=54)\) d. \(\operatorname{Sr}(Z=38)\)

Short answer

The simple Lewis structures for the given elements are: a. Iodine (I): \[ \overset{..}{\underset{..}{\underset{..I}{}}}..\] b. Aluminum (Al): \[ \overset{..}{\underset{..}{\underset{.Al}{}}} \] c. Xenon (Xe): \[ \overset{..}{\underset{..}{\underset{..Xe}{}}}..\:.. \|..\] d. Strontium (Sr): \[ \overset{..}{\underset{..}{\underset{.Sr}{}}} \]

Step-by-step solution

Determine the number of valence electrons

To find the number of valence electrons for each element, refer to the main group number in the periodic table. The main group number corresponds to the number of valence electrons. a. Iodine (I) - Group 17, has 7 valence electrons. b. Aluminum (Al) - Group 13, has 3 valence electrons. c. Xenon (Xe) - Group 18, has 8 valence electrons. d. Strontium (Sr) - Group 2, has 2 valence electrons. 2. Draw the simple Lewis structures for each element Using the determined number of valence electrons, draw the Lewis structures for each element by representing the symbol of the element and placing the valence electrons as dots around the symbol.

Draw the simple Lewis structures

For each element, draw its symbol and arrange the valence electrons as dots surrounding the symbol. Place the electrons in pairs where necessary. a. Iodine (I): \[ \overset{..}{\underset{..}{\underset{..I}{}}}..\] b. Aluminum (Al): \[ \overset{..}{\underset{..}{\underset{.Al}{}}} \] c. Xenon (Xe): \[ \overset{..}{\underset{..}{\underset{..Xe}{}}}..\:.. \|..\] d. Strontium (Sr): \[ \overset{..}{\underset{..}{\underset{.Sr}{}}} \] These are the simple Lewis structures for the elements Iodine (I), Aluminum (Al), Xenon (Xe), and Strontium (Sr).

Key concepts

Valence Electrons

Valence electrons are the electrons located in the outermost shell of an atom that determine its chemical properties and its ability to bond with other atoms. They play a pivotal role in forming chemical bonds, as they can be lost, gained, or shared in the process of creating molecules.

In the context of the exercise, understanding valence electrons is crucial for drawing Lewis structures. The number of valence electrons is directly associated with the group number of elements in the periodic table for main group elements. For instance, elements in Group 1 have 1 valence electron, whereas those in Group 17 have 7, as seen with iodine (I). Group 18 elements, the noble gases, typically have 8 valence electrons, giving them a special status because they are generally inert and do not form bonds easily.

When drawing Lewis structures, the valence electrons are represented as dots around the symbol for the element, which allows us to visualize the possible bonds an atom can form. In some cases, electrons are paired to show the potential for bond formation, such as a shared pair between two atoms in a covalent bond.

Periodic Table

The periodic table is an organized chart of all known chemical elements, arranged by increasing atomic number, electron configurations, and recurring chemical properties. Elements are sorted into rows, known as periods, and columns, referred to as groups or families.

For the task at hand, the periodic table helps us ascertain the valence electrons of elements—you simply look at the group number for main group elements. The periodic table also indicates the elements' general chemical behavior. For example, elements in Group 1 are highly reactive metals, while Group 18 contains the noble gases, which are generally non-reactive due to having a full valence electron shell.

Furthermore, the table aids in predicting how elements are likely to bond and the type of compounds they will form. In drawing Lewis structures, this knowledge is fundamental because it shows the 'big picture' of how an element's position in the periodic table influences its chemical properties, especially those related to bonding and stability.

Chemical Elements

Chemical elements are the simplest form of matter that cannot be broken down into simpler substances by chemical means. Each element is defined by the number of protons it has in its nucleus, known as the atomic number (Z). Elements possess unique properties which determine how they interact with other elements to form compounds.

As seen in the exercise, knowing the atomic number of an element such as Iodine (Z=53) or Xenon (Z=54) not only helps identify the element but also provides information about its electronic structure. The number of valence electrons, which affects an element's chemical reactivity and the types of bonds it can form, can typically be deduced from its position on the periodic table.

In terms of Lewis structures, each element's individual characteristics are symbolized through the representation of their valence electrons. This visual representation serves as a foundational concept in understanding the behavior of elements in chemical reactions and is a cornerstone of many aspects of chemistry, including bonding, reactivity, and molecule formation.