Problem 6 - Anatomy and Physiology of Animals

Question

A cation has a(n) charge. a. neutral b. positive C. alternating d. negative

Step-by-Step Solution

Answer

A cation has a positive charge.

Step 1: Understanding Cation

A cation is an ion that has lost one or more of its electrons, resulting in a positive charge. Ions are atoms or molecules with a net electrical charge due to the loss or gain of electrons. Cations specifically refer to positively charged ions.

Step 2: Identifying the Charge

Positive ions are created when an atom loses electrons, which results in a higher number of protons than electrons in the atom. Since protons carry a positive charge and are now more in number than the negatively charged electrons, the atom exhibits a net positive charge.

Step 3: Evaluating the Options

Examine each choice: (a) Neutral - This would imply the atom has an equal number of protons and electrons. Therefore not charged. (b) Positive - This agrees with the definition of a cation. (c) Alternating - There is no concept of alternating charge in ions; ions have a fixed net charge. (d) Negative - This defines an anion, not a cation.

Step 4: Concluding the Correct Answer

Based on the understanding and evaluation of the definitions and options, the correct answer is (b) Positive, as it matches the definition of a cation.

Key Concepts

Ions

In chemistry, ions are simply atoms or molecules that have either gained or lost electrons, resulting in a net electrical charge. When an atom or molecule acquires charge through electron movement, it turns into an ion. Ions are classified into two main types based on the nature of their charge:

• Cations – possess a positive charge.
• Anions – possess a negative charge.

The formation of ions plays a crucial role in various chemical reactions and compounds. When atoms gain electrons, they have more electrons than protons, making them anions. Conversely, by losing electrons, they become cations. Ions seek to achieve stability and often engage in bonding with other atoms to reach a stable electronic configuration.
Understanding ions is essential in chemistry, as their interactions influence the properties and behaviors of elements and compounds in both simple and complex reactions.

Cations

Cations are a specific type of ion characterized by their positive charge. The term "cation" originates from the Greek word 'kation,' meaning 'going down,' which provides a hint about the loss of electrons. When an atom loses electrons, which are negatively charged, it becomes a cation because the balance shifts to more positive protons.

• The loss of electrons results in fewer negative charges compared to positive charges.
• Cations typically form from metals, as metals tend to lose electrons easily.

A few examples of common cations include sodium ( ext{Na}^+), calcium ( ext{Ca}^{2+}), and aluminum ( ext{Al}^{3+}).
Recognizing cations is essential for predicting how substances interact chemically, as these ions often link up with anions to form ionic compounds.

Positive charge

A positive charge occurs when there are more protons than electrons in an atom or molecule. Protons, found in the nucleus, naturally carry a positive charge. When electrons, which carry a negative charge, are lost, the net result is a positive charge.

• Protons are inherently positive.
• A loss of electrons creates an imbalance, leading to a positive charge.

The concept of positive charge is central to understanding cations. In a cation, the deficiency in electrons compared to protons results in such a charge. This positive charge allows cations to participate in bonding by attracting negatively charged ions, or anions, forming structures crucial to many chemical compounds and reactions.

Electrons

Electrons are fundamental subatomic particles carrying a negative charge, residing in the space surrounding an atomic nucleus. They play a vital role in chemical bonding and reactions.

• Electrons possess a negative charge, perfectly balancing the positive charge of protons in a neutral atom.
• The position and number of electrons determine how an atom interacts with others.

Changes in electron count lead to ion creation. When an atom loses electrons, reducing its total negative charge, it turns into a cation with a positive charge. This is key to understanding why atoms with electron deficits form cations. The behavior of electrons dictating ionization also underpins much of what governs physical and chemical transformations at the atomic level.