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Ch.8 - Basic Concepts of Chemical Bonding
Chapter 8, Problem 32

Which of these elements are unlikely to form ionic bonds: Mg, Al, Si, Br, I?

Verified step by step guidance
1
Step 1: Understand the nature of ionic bonds. Ionic bonds are formed between metals and non-metals where electrons are transferred from the metal to the non-metal, resulting in the formation of positively charged cations and negatively charged anions.
Step 2: Identify the elements given in the problem. The elements are Mg (Magnesium), Al (Aluminum), Si (Silicon), Br (Bromine), and I (Iodine).
Step 3: Classify each element as a metal, non-metal, or metalloid. Mg and Al are metals, Si is a metalloid, and Br and I are non-metals.
Step 4: Determine the likelihood of each element forming ionic bonds. Metals like Mg and Al tend to lose electrons and form cations, making them likely to form ionic bonds with non-metals. Non-metals like Br and I tend to gain electrons and form anions, also making them likely to form ionic bonds with metals.
Step 5: Consider the metalloid Si. Metalloids have properties intermediate between metals and non-metals and are less likely to form ionic bonds. Instead, they often form covalent bonds. Therefore, Si is unlikely to form ionic bonds.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Ionic Bonds

Ionic bonds are formed when one atom donates an electron to another, resulting in the creation of positively and negatively charged ions. This typically occurs between metals, which lose electrons, and nonmetals, which gain electrons. The electrostatic attraction between these oppositely charged ions holds them together in a compound.
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Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. Elements with high electronegativity, such as nonmetals, are more likely to gain electrons and form ionic bonds with metals. Conversely, elements with low electronegativity are less likely to form ionic bonds, as they do not readily accept electrons.
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Metallic vs. Nonmetallic Character

The metallic character of an element refers to its tendency to lose electrons and form positive ions, while nonmetallic character indicates a tendency to gain electrons. Metals like magnesium (Mg) and aluminum (Al) are more likely to form ionic bonds due to their metallic nature, whereas elements like silicon (Si), bromine (Br), and iodine (I) exhibit more nonmetallic characteristics, making them less likely to form ionic bonds.
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