Question

Write the formula for each of the following carboncontaining ions, including the overall charge of the ions. a. carbonate b. hydrogen carbonate c. acetate d. cyanide

Short answer

a. \(CO_3^{2-}\) b. \(HCO_3^-\) c. \(CH_3COO^-\) or \(C_2H_3O_2^-\) d. \(CN^-\)

Step-by-step solution

a. Carbonate Ion

The carbonate ion is composed of one carbon atom and three oxygen atoms. The overall charge of the carbonate ion is 2-. Therefore, the chemical formula for the carbonate ion is \(CO_3^{2-}\).

b. Hydrogen Carbonate Ion

The hydrogen carbonate ion, also known as bicarbonate ion, is composed of one hydrogen atom, one carbon atom, and three oxygen atoms. The overall charge of the hydrogen carbonate ion is 1-. Therefore, the chemical formula for the hydrogen carbonate ion is \(HCO_3^-\).

c. Acetate Ion

The acetate ion is composed of two carbon atoms, three hydrogen atoms, and two oxygen atoms. The overall charge of the acetate ion is 1-. Therefore, the chemical formula for the acetate ion is \(CH_3COO^-\) or \(C_2H_3O_2^-\).

d. Cyanide Ion

The cyanide ion is composed of one carbon atom and one nitrogen atom. The overall charge of the cyanide ion is 1-. Therefore, the chemical formula for the cyanide ion is \(CN^-\).

Key concepts

Carbonate Ion

The carbonate ion is a well-known polyatomic ion that is crucial in both chemistry and earth sciences. Composed of one carbon atom covalently bonded to three oxygen atoms, it belongs to the family of oxoanions, where oxygen takes a key role in the structure. The carbonate ion carries an overall charge of -2, which is indicated as a superscript in its chemical formula, written as \(CO_3^{2-}\).
The presence of a negative charge signifies the tendency of the carbonate ion to combine with positively charged ions to form compounds like calcium carbonate, which is prevalent in rocks and shells. Understanding the carbonate ion is essential in fields ranging from geology to environmental science.

• Composed of: 1 carbon atom, 3 oxygen atoms
• Overall charge: -2
• Formula: \(CO_3^{2-}\)

Acetate Ion

The acetate ion, represented by \(CH_3COO^-\) or \(C_2H_3O_2^-\), is commonly encountered in organic chemistry. As the ionized form of acetic acid, it features two carbon atoms: one forming part of a carboxyl group with an oxygen, and the other bonded to three hydrogens. The acetate ion is integral in biological systems as well as industrial applications.
Its negative charge of -1 makes it a useful component in salts and esters, playing roles in reactions like fermentation and metabolism. This ion is known for its presence in vinegar, where it imparts the characteristic sour flavor due to its origin from acetic acid.

• Composed of: 2 carbon atoms, 3 hydrogen atoms, 2 oxygen atoms
• Overall charge: -1
• Formula: \(CH_3COO^-\) or \(C_2H_3O_2^-\)

Cyanide Ion

The cyanide ion is a simple yet powerful ion composed of one carbon and one nitrogen atom, bonded together in a linear arrangement. Represented as \(CN^-\), it carries a single negative charge. This ion is known for its potent reactivity, being able to form complexes with metals and pivotal in processes like gold and silver extraction.
Due to its high toxicity, inspiring caution in handling, the cyanide ion plays critical roles in industrial processes. It's seen in chemical synthesis and even in some biological systems, where it requires careful regulation to prevent harm.

• Composed of: 1 carbon atom, 1 nitrogen atom
• Overall charge: -1
• Formula: \(CN^-\)

Ions

In chemistry, ions are atoms or molecules that have gained or lost one or more electrons, resulting in a net electrical charge. Ions can be either positively charged (cations) or negatively charged (anions). This charge affects the chemical nature of the ion, influencing its ability to bond with other particles.
The process of gaining or losing electrons to form ions is critical in the formation of chemical compounds. The behavior of ions, such as those in salts or acids, underpins a wide array of chemical reactions and phenomena.

• Types: Cations (+ charge), Anions (- charge)
• Formed by electron gain/loss
• Critical in chemical reactions

Chemical Charge

Chemical charge refers to the electrical charge that an ion possesses. It results from an imbalance between the number of protons (positive charges) and electrons (negative charges). Chemical charge is paramount in determining how ions interact with each other.
Positive charges exist when there are fewer electrons than protons, while negative charges occur when there are more electrons. The chemical charge is expressed as a superscript in chemical formulas, such as \(CO_3^{2-}\) for the carbonate ion.

• Caused by proton-electron imbalance
• Indicates bonding potential
• Shown as a superscript in formulas