Question

Positive ions are called __________, whereas negative ions are called _________.

Short answer

Positive ions are called cations, whereas negative ions are called anions.

Step-by-step solution

Recognize Positive Ions

Positive ions are atoms or molecules that have lost one or more electrons, resulting in a net positive charge. These ions are also known as cations. #Step 2: Understanding Negative Ions#

Recognize Negative Ions

Negative ions are atoms or molecules that have gained one or more electrons, resulting in a net negative charge. These ions are also known as anions. #Step 3: Filling in the Blanks#

Complete the sentence

Now that we know the terms for positive and negative ions, we can fill in the blanks: Positive ions are called cations, whereas negative ions are called anions.

Key concepts

Cations

Cations are ions with a net positive charge. This happens when an atom or molecule loses one or more of its electrons. Electrons are negatively charged, so losing them results in a net positive charge.
Here’s why cations form:

• Atoms seek stability. By shedding electrons, they often reach a more stable, lower energy state.
• Many metals lose electrons to become positive ions. For example, when a sodium atom (Na) loses an electron, it becomes a sodium cation (\( \text{Na}^+ \)).

Cations have crucial roles in chemistry and biology. For instance, the sodium cation helps transmit nerve signals in our bodies.
To identify a cation, look for a plus sign (\( ^+ \)) after the chemical symbol, indicating a positive charge.

Anions

Anions are ions with a net negative charge because they have gained extra electrons. Electrons have a negative charge, so gaining them makes the overall charge of the particle negative.
The formation of anions typically occurs in the following scenarios:

• Non-metal elements tend to gain electrons to become more stable, much like reaching a complete outer electron shell.
• Chlorine, for example, gains an electron to form a chloride anion (\( \text{Cl}^- \)). This anion is significant in forming common table salt when combined with sodium cations.

Anions are vital in creating compounds, especially salts and other ionic compounds. These compounds are formed by the attraction between oppositely charged cations and anions.
To spot an anion, look for a negative sign (\( ^- \)) after the chemical symbol, which points to a gained electron resulting in a negative charge.

Charge of Ions

The charge of ions plays a vital role in understanding chemical reactions and compounds' formation. When atoms gain or lose electrons, they no longer remain neutral and acquire charges as ions.
Here's how the charge of an ion is determined:

• Cations form by losing electrons and carry a positive charge. The charge's magnitude corresponds to the number of electrons lost. For instance, if an atom loses two electrons, it will have a \( 2^+ \) charge.
• Anions form by gaining electrons and bear a negative charge. Similarly, the number of gained electrons determines the charge's magnitude. If an atom gains three electrons, its charge will be \( 3^- \).

Understanding ionic charge is fundamental for predicting the behavior of ionic compounds in reactions, such as reactivity and solubility.
When you examine ions in chemical equations, note the charge. It guides you in balancing equations and deducing the chemical reactions' outcomes.