Question

Write the correct chemical name for each compound. (Chapter 7\()\) a. Nal b. Fe \(\left(\mathrm{NO}_{3}\right)_{3}\) c. \(\operatorname{Sr}(\mathrm{OH})_{2}\) d. \(\mathrm{CoCl}_{2}\) e. \(\mathrm{Mg}\left(\mathrm{BrO}_{3}\right)_{2}\)

Short answer

Answer: a. Sodium iodide

Step-by-step solution

a. Nal

1. Cation is Na (sodium) and anion is I (iodine). 2. No need to determine the oxidation states for monatomic ions. 3. Combine the names: Sodium iodide.

Key concepts

Ionic Compounds

Ionic compounds consist of two elements: a metal and a nonmetal. These compounds form when atoms either gain or lose electrons, creating ions. In ionic bonding, oppositely charged ions attract each other. For example, in the compound NaI, sodium ( Na ) loses an electron to become positively charged ( Na^+ ), while iodine ( I ) gains that electron to become negatively charged ( I^- ). This transfer creates a bond due to the attraction between the positive and negative ions.

• Formation: Ionic bonds form typically between metals and nonmetals.
• Electron Transfer: Metals donate electrons, becoming positive ions. Nonmetals accept electrons, becoming negative ions.
• Properties: Ionic compounds are usually solid at room temperature and can conduct electricity when melted or dissolved in water.

Understanding the nature of ionic compounds is crucial in naming them and predicting their properties.

Monatomic Ions

Monatomic ions are ions composed of a single atom with a positive or negative charge. They result from atoms that gain or lose electrons to achieve a full outer electron shell, often following the octet rule. A common example is the sodium and iodine in sodium iodide ( NaI ): Sodium becomes Na^+ by losing one electron, and iodine becomes I^- by gaining an electron.

• Simple Ions: Monatomic ions include easily recognizable ions like Na^+ , Cl^- , K^+ , and O^{2-} .
• Charge Determination: The periodic table helps determine common charges for monatomic ions: group 1 elements form +1 ions, group 2 form +2 ions, and so on.
• Stability: These ions are stable due to their electron configurations, similar to noble gases.

Focusing on the nature and charge of monatomic ions helps in identifying and balancing chemical compounds.

Oxidation States

Oxidation states, or oxidation numbers, indicate the degree of oxidation of an atom in a compound. This concept helps in determining the electron distribution among the atoms in a molecule. In simple ionic compounds, the oxidation state corresponds to the charge of the ion. For sodium iodide ( NaI ), Na is in the +1 oxidation state (since it loses one electron) and I is in the -1 oxidation state.

• Purpose: Oxidation states help identify how electrons transfer in redox reactions.
• Simplifying Compounds: They help in balancing chemical equations and understanding the charge balance within a compound.
• Consistent Rules: Common rules include elements in their natural state having zero oxidation states, and the sum of oxidation states in a neutral compound being zero.

By applying oxidation state rules, students can better grasp the nature of chemical compounds and predict reactions.

Chemical Naming Rules

The rules for naming chemical compounds help to provide a unique and universally accepted language in chemistry. For ionic compounds, the naming process starts with identifying the cation and anion. The cation, often a metal, is named first, followed by the anion, which is a nonmetal, ending with '-ide'. For example, in NaI, sodium is the cation and iodine changes to iodide, resulting in the name 'sodium iodide'.

• Simple Ionic Compounds: Name the metal first followed by the nonmetal with an '-ide' suffix.
• Transition Metals: When transition metals are involved, indicate the oxidation state with Roman numerals (e.g., Fe(NO_3)_3 is iron(III) nitrate).
• Polyatomic Ions: If the compound includes polyatomic ions, use the name of the polyatomic ion without changing its ending (e.g., Sr(OH)_2 is strontium hydroxide).

Grasping these naming conventions is essential to effectively communicate chemical compounds across different contexts.