Question

Give the formula for each of the following: a. carbon monoxide b. diphosphorus pentoxide \(\underline{\mathbf{c}}\) dihydrogen sulfide d. sulfur dichloride

Short answer

The formulas are: a. CO, b. P2O5, c. H2S, d. SCl2

Step-by-step solution

Understand the Prefixes

Chemical formulas are derived based on the prefixes that indicate the number of atoms. Knowing these prefixes is crucial: - 'Mono-' means 1 - 'Di-' means 2 - 'Tri-' means 3 - 'Tetra-' means 4 - 'Penta-' means 5

Carbon Monoxide (CO)

The prefix 'Mono-' indicates one oxygen atom. Thus, carbon monoxide is composed of one carbon atom and one oxygen atom: Carbon Monoxide (CO)

Diphosphorus Pentoxide (P2O5)

The prefix 'Di-' indicates two phosphorus atoms, and 'Penta-' indicates five oxygen atoms. Therefore, diphosphorus pentoxide is composed of two phosphorus atoms and five oxygen atoms:Diphosphorus Pentoxide (P2O5)

Dihydrogen Sulfide (H2S)

The prefix 'Di-' indicates two hydrogen atoms. 'Sulfide' denotes one sulfur atom. Thus, dihydrogen sulfide is composed of two hydrogen atoms and one sulfur atom:Dihydrogen Sulfide (H2S)

Sulfur Dichloride (SCl2)

The prefix 'Di-' indicates two chlorine atoms. Sulfur does not require a prefix since there's only one sulfur atom. Therefore, sulfur dichloride has one sulfur atom and two chlorine atoms:Sulfur Dichloride (SCl2)

Key concepts

Nomenclature

Nomenclature in chemistry refers to the system of names used to identify different chemical compounds. This system ensures that each compound has a unique and universally accepted name, which makes it easier for scientists around the world to communicate effectively.
There are two main types of nomenclature:

• IUPAC Nomenclature: This is a standardized system set by the International Union of Pure and Applied Chemistry (IUPAC) and is widely used for naming organic and inorganic compounds.
• Common Nomenclature: These are traditional names that might not follow strict rules but are commonly used and understood, such as 'water' for H₂O.

The naming of molecular compounds in particular often uses prefixes to denote the number of atoms involved, ensuring clarity and precision.

Prefixes in Chemistry

In chemistry, prefixes are used to indicate the number of atoms of each element in a compound. This is especially crucial for naming molecular compounds, which are formed by two nonmetals.
Here's a list of common prefixes and what they represent:

• Mono- means 1
• Di- means 2
• Tri- means 3
• Tetra- means 4
• Penta- means 5
• Hexa- means 6
• Hepta- means 7
• Octa- means 8
• Nona- means 9
• Deca- means 10

For example, in 'carbon monoxide' (CO), the prefix 'mono-' shows that there is one oxygen atom. In 'diphosphorus pentoxide' (P₂O₅), 'di-' denotes two phosphorus atoms and 'penta-' denotes five oxygen atoms.
Using these prefixes accurately helps in understanding and naming the exact composition of compounds.

Composition of Compounds

The composition of a compound refers to the types and numbers of atoms that make up the compound. Understanding composition helps to determine a compound's chemical formula and properties.
Chemical formulas are a concise way of expressing information about the atoms in a compound. For example:

• Carbon Monoxide (CO): One carbon atom is bonded to one oxygen atom.
• Diphosphorus Pentoxide (P₂O₅): Two phosphorus atoms are bonded to five oxygen atoms.
• Dihydrogen Sulfide (H₂S): Two hydrogen atoms are bonded to one sulfur atom.
• Sulfur Dichloride (SCl₂): One sulfur atom is bonded to two chlorine atoms.

The chemical formula is derived based on the prefixes used in the name of the compound. Knowing the composition not only helps in determining the formula but also in predicting the behavior and reactivity of the compound in chemical reactions.