Question

Write the name for each of the following: a. \(\mathrm{Ag}_{3} \mathrm{P}\) b. PbS c. \(\mathrm{SnO}_{2}\) d. \(\mathrm{MnCl}_{3}\) e. FeS f. \(\mathrm{CoCl}_{2}\)

Short answer

a. Silver Phosphide, b. Lead(II) Sulfide, c. Tin(IV) Oxide, d. Manganese(III) Chloride, e. Iron(II) Sulfide, f. Cobalt(II) Chloride

Step-by-step solution

Name the compound \( \mathrm{Ag}_{3} \mathrm{P} \)

The compound \( \mathrm{Ag}_{3} \mathrm{P} \) consists of silver (Ag) and phosphorus (P). Silver typically carries a +1 charge. Since there are three silvers, each carrying a +1 charge, the single phosphorus must have a -3 charge. Thus, the name of the compound is Silver Phosphide.

Name the compound PbS

The compound PbS consists of lead (Pb) and sulfur (S). Lead can have multiple oxidation states, but in this compound, it takes on a +2 charge to balance the -2 charge of sulfur. Therefore, the name is Lead(II) Sulfide.

Name the compound \( \mathrm{SnO}_{2} \)

The compound \( \mathrm{SnO}_{2} \) consists of tin (Sn) and oxygen (O). Tin can have a +4 oxidation state, which is necessary to balance the -2*2 from the two oxygens. Hence, the name of the compound is Tin(IV) Oxide.

Name the compound \( \mathrm{MnCl}_{3} \)

The compound \( \mathrm{MnCl}_{3} \) is composed of manganese (Mn) and chlorine (Cl). Chlorine typically carries a -1 charge, and since there are three chlorines, manganese must have a +3 charge to balance. Thus, the compound is named Manganese(III) Chloride.

Name the compound FeS

The compound FeS consists of iron (Fe) and sulfur (S). Iron can have multiple oxidation states, but in this case, it has a +2 charge to balance the -2 charge of sulfur. Hence, the name is Iron(II) Sulfide.

Name the compound \( \mathrm{CoCl}_{2} \)

The compound \( \mathrm{CoCl}_{2} \) comprises cobalt (Co) and chlorine (Cl). Chlorine typically carries a -1 charge and, with two chlorines, cobalt has a +2 charge to maintain neutrality. Therefore, the name is Cobalt(II) Chloride.

Key concepts

Chemical Nomenclature

Chemical nomenclature is a system used to name chemical compounds. The International Union of Pure and Applied Chemistry (IUPAC) sets the rules for naming chemicals.
Naming ionic compounds involves combining the names of the positive ion (cation) and the negative ion (anion). Some common elements and polyatomic ions have specific names that must be memorized.
Here's a simplified guide:

• First, determine the cation (typically a metal).
• Next, identify the anion (usually a non-metal or a group of atoms).
• Combine these names. For a simple binary compound (one metal, one non-metal), just combine the names with the cation first.
• For transition metals that can have multiple charges, indicate the charge with Roman numerals in parentheses after the cation name.

For example, PbS is named Lead(II) Sulfide because lead can have multiple oxidation states, and the (II) indicates a +2 charge to balance the -2 charge from sulfur. This systematic approach ensures that anyone familiar with the rules can deduce the formula and composition of a compound from its name.

Oxidation States

Oxidation states (or oxidation numbers) represent the number of electrons that an atom gains, loses, or shares when it forms chemical bonds. They help in understanding the electron transfer between atoms in ionic compounds.
Some key points include:

• The oxidation state of an element in its pure form is zero (e.g., O2, N2).
• In a simple ion, the oxidation state corresponds to the charge of the ion (e.g., Na+ has +1, Cl- has -1).
• For polyatomic ions and compounds, the sum of oxidation states must equal the overall charge.

When naming compounds, it's essential to deduce the oxidation state, especially for transition metals. For instance, in the compound SnO2, oxygen has a -2 oxidation state. With two oxygens, this totals -4, meaning Sn must have a +4 state to balance it out, naming the compound Tin(IV) Oxide. This systematic rule ensures clarity in compound identification and communication.

Ionic Compounds

Ionic compounds are formed through the electrostatic attraction between cations and anions. These compounds are typically formed between metals and non-metals.
Here's how they are created:

• An atom loses one or more electrons (forming a cation).
• Another atom gains those electrons (forming an anion).
• The opposite charges attract, creating a stable compound.

For example, in the compound \({Ag_3P}\), silver (Ag) acts as the cation and phosphorus (P) as the anion. Since silver typically has a +1 charge and phosphorus takes on a -3 charge, three silver atoms are needed to balance one phosphorus, leading to the formula \({Ag_3P}\), named Silver Phosphide. Ionic compounds are generally solid and have high melting and boiling points. Their intricate lattice structures contribute to physical properties such as hardness and brittleness. Understanding these basics helps in grasping the formation and behavior of ionic compounds in various chemical reactions.