Question

Give the proper formula for each name. a) chlorine dioxide b) selenium dibromide c) dinitrogen trioxide

Short answer

a) \( ClO_2 \), b) \( SeBr_2 \), c) \( N_2O_3 \)

Step-by-step solution

Understanding prefixes and elements

To name a molecule, prefixes indicate the number of each type of atom in the molecule. 'Mono-' indicates one, 'di-' indicates two, and 'tri-' indicates three. Elements in a compound are denoted using their chemical symbols from the periodic table.

Determine the formula for chlorine dioxide

The name 'chlorine dioxide' consists of 'chlorine' and 'dioxide'. The prefix 'di-' indicates two oxygen atoms are present. Therefore, the formula is \( ClO_2 \).

Determine the formula for selenium dibromide

The name 'selenium dibromide' consists of 'selenium' and 'dibromide'. The prefix 'di-' indicates two bromine atoms are present. This gives the formula \( SeBr_2 \).

Determine the formula for dinitrogen trioxide

The name 'dinitrogen trioxide' consists of 'dinitrogen' and 'trioxide'. The prefix 'di-' indicates two nitrogen atoms and 'tri-' indicates three oxygen atoms. Thus, the formula is \( N_2O_3 \).

Key concepts

Molecular Formulas

Molecular formulas represent the types and numbers of atoms present in a molecule. For example, the molecular formula for water is \( H_2O \), which indicates that each water molecule contains two hydrogen atoms and one oxygen atom. Understanding molecular formulas is crucial in chemistry because it conveys how atoms combine in specific ratios to form compounds.
Molecular formulas are abstraction, breaking down compound elements into symbols and numbers. Here are a few things to keep in mind about them:

• Atoms are represented by their elemental chemical symbols from the periodic table.
• Numbers written as subscripts next to elemental symbols indicate the quantity of that atom.
• Without a subscript, it implies there is only one atom of that element in the compound.

By grasping molecular formulas, you learn about the hidden language of chemistry, where elements speak through symbols and numbers that determine a compound's structure and properties.

Prefixes in Chemistry

Prefixes in chemistry are a fundamental way to express the quantity of an element within a compound. They are especially useful in molecular compounds composed of nonmetals. Learning these prefixes allows you to accurately determine the number of atoms needed for a given element in a molecular formula.
Here are some commonly used prefixes in chemistry:

• "Mono-" means one.
• "Di-" indicates two.
• "Tri-" signifies three.
• "Tetra-" stands for four.
• "Penta-" means five.
• "Hexa-" is six.

It's important to note that these prefixes are used to remove ambiguity when naming molecular compounds. When you hear a name like "dinitrogen trioxide," it immediately tells you, thanks to the prefixes, that there are two nitrogen atoms and three oxygen atoms in the molecule.

Chemical Symbols

Chemical symbols are shorthand representations of elements, derived from their names and used universally in the scientific community. They provide an efficient way to communicate information about the elements and compounds in written form.
Understanding chemical symbols is critical for interpreting molecular formulas, as they allow you to identify the specific atoms involved:

• Most chemical symbols consist of one or two letters, with the first letter always capitalized.
• Some symbols, like \(Cl\) for chlorine and \(Br\) for bromine, are directly tied to the elements' English names.
• Others, such as \(Fe\) for iron (from Latin "ferrum") or \(Na\) for sodium (from Latin "natrium"), are derived from Latin names.

A solid grasp of chemical symbols enables you to seamlessly translate between the verbal names of compounds and their symbolic molecular formulas.

Systematic Naming

Systematic naming, or chemical nomenclature, refers to a set of rules used to generate the names of chemical compounds in a way that conveys their composition. This standardization is essential because it ensures that everyone who reads a chemical name understands exactly what it comprises.
The process of systematic naming involves using:

• Prefixes to indicate the number of atoms of each element present.
• The base name of the elements involved, usually ending with the element listed second in an altered form, such as "oxide" for oxygen.
• Ordering elements properly, often by convention such that the more electronegative elements are listed first.

This approach makes it straightforward to both name a compound based on its formula and deduce a formula from its name. For example, the name "selenium dibromide" can be systematically deconstructed to learn that the formula is \(SeBr_2\), meaning it consists of one selenium atom and two bromine atoms.