I CAN name simple compounds from chemical formulas and recognize the chemical names of everyday substances.

I CAN infer the relationship among chemical formulas, composition, and name for substances such as acids, bases, and salts.

Which One Doesn't Belong

Think-pair-share

What do you think chemical structures represent?

How do you think chemists name them?

Record your thoughts on your handout.

What are some substandes you use daily? What are their chemical names? You may remember some of these from the previous chapter. 

The periodic table is a diagram outlining all the elements that have been discovered.

Go to the Element Matching Game. Try to go from the level EASY to EXPERT.

Nomenclature rules are used to name elements and compounds based on their chemical formulas.

Elements: 

An element is a pure substance that consists of only one type of atom, characterized by its number of protons in the nucleus, known as the atomic number. Each element is represented by a unique chemical symbol (e.g., H for hydrogen, O for oxygen).

There are currently 118 known elements, and they are organized in the Periodic Table based on their atomic number, electron configuration, and recurring chemical properties.

Key properties of elements include:

• Atomic number: The number of protons in the nucleus of an atom, which defines the element.

• Atomic mass: The average mass of an element’s atoms, accounting for the different isotopes of that element.

• Chemical behavior: Elements have distinct chemical properties, such as reactivity, bonding behavior, and electron configuration, which determine how they interact with other elements.

Examples of elements include:

• Hydrogen (H): The simplest element, consisting of just one proton and one electron.

• Oxygen (O): An element essential for respiration and combustion.

• Iron (Fe): A metal used in construction and manufacturing.

Elements can combine to form compounds, which are substances made up of two or more different elements bonded together chemically (e.g., H₂O, water, is made of hydrogen and oxygen atoms).

Types of Compounds:

1. Ionic Compounds:

   • Formed when electrons are transferred from one atom to another, creating positive and negative ions that attract each other.

   • Typically, ionic compounds consist of a metal and a non-metal.

   • Example: Sodium chloride (NaCl) – formed from sodium (Na) and chlorine (Cl).

2. Covalent Compounds (Molecular Compounds):

   • Formed when two or more non-metal atoms share electrons.

   • These compounds usually have a molecular structure where the atoms are held together by covalent bonds.

   • Example: Water (H₂O) – formed from hydrogen (H) and oxygen (O).

Properties of Compounds:

• Distinct properties: The properties of a compound are often very different from the properties of the elements that make it up. For example, sodium is a highly reactive metal, and chlorine is a poisonous gas, but when they combine to form sodium chloride (NaCl), it becomes a stable, non-toxic salt.

• Fixed ratios: The elements in a compound combine in a specific, fixed ratio (e.g., in water, two hydrogen atoms combine with one oxygen atom: H₂O).

Examples of Compounds:

1. Water (H₂O): A compound made of two hydrogen atoms and one oxygen atom.

2. Carbon dioxide (CO₂): A compound made of one carbon atom and two oxygen atoms.

3. Sodium chloride (NaCl): A compound made of one sodium atom and one chlorine atom.

Compounds can be organic (containing carbon) or inorganic (not containing carbon, although carbon can also be part of inorganic compounds in certain cases).

Naming Ionic Compounds (Metal + Non-metal)

Step 1: Name the metal first.

• • Metals are usually on the left side of the Periodic Table.

  • Example: Sodium (Na), Magnesium (Mg).

Step 2: Name the non-metal second, but change the ending to “-ide.”

• • Non-metals are on the right side of the Periodic Table.

  • Example: Chlorine becomes Chloride, Oxygen becomes Oxide.

Example 1: 

NaCl (Sodium chloride)

• • Sodium (metal) + Chlorine (non-metal) → Sodium chloride.

Example 2: 

MgO (Magnesium oxide)

• • Magnesium (metal) + Oxygen (non-metal) → Magnesium oxide.

Naming Covalent Compounds (Non-metal + Non-metal)

Step 1: Name the first non-metal as usual.

• • If there is more than one atom of the element, use a prefix (e.g., mono-, di-, tri-) to indicate the number.

Step 2: Name the second non-metal next

• • but change the ending to “-ide.”

  • add a prefix for the number of atoms.

Common Prefixes:

• • Mono- (1), Di- (2), Tri- (3), Tetra- (4), Penta- (5), etc.

Example 1: 

CO₂ (Carbon dioxide)

• • Carbon (1 atom) + Oxygen (2 atoms) → Carbon dioxide.

Example 2:

N₂O₅ (Dinitrogen pentoxide)

• • Nitrogen (2 atoms) + Oxygen (5 atoms) → Dinitrogen pentoxide.

Naming Acids (Compounds that contain hydrogen)

Step 1: If the compound is a binary acid (hydrogen + one non-metal), use “hydro-” and change the non-metal’s ending to “-ic,” followed by “acid.”
Example 1: 

HCl (Hydrochloric acid)

• • Hydrogen + Chlorine → Hydrochloric acid.

Step 2: If the compound is an oxyacid (hydrogen + polyatomic ion), the suffix of the ion changes:

• • -ate becomes -ic acid.

  • -ite becomes -ous acid.

• Example 1: 

H₂SO4 (Sulfuric acid)

• • Hydrogen + Sulfate (SO4²⁻) → Sulfuric acid.

Compound Naming Practice Worksheet

Answers