Chemical Names And Formula Flashcards
What is a chemical name?
The full name of a substance.
What is a chemical formula?
It states the types of atoms in a substance and their ratio.
How do you write the chemical formula of lithium oxide?
Step 1: Identify the cation. Lithium (Li) is in Group 1, so it loses 1 electron to form Li⁺. Step 2: Identify the anion. Oxygen (O) is in Group 16, so it gains 2 electrons to form O²⁻. Step 3: Balance charges. Two Li⁺ ions are needed to balance one O²⁻ ion. Chemical formula: Li₂O.
What is a variable charge in an ion?
Some atoms can have different charges, indicated with Roman numerals (e.g., Iron (II) or Iron (III)).
How do you write the chemical formula of iron (III) sulfide?
Step 1: Identify the cation. Fe³⁺. Step 2: Identify the anion. S²⁻. Step 3: Balance charges. Two Fe³⁺ ions balance three S²⁻ ions. Chemical formula: Fe₂S₃.
What is a polyatomic ion?
A group of atoms that reacts as a single unit and carries a charge.
How do you write the chemical formula of calcium hydroxide?
Step 1: Identify the cation. Ca²⁺. Step 2: Identify the polyatomic anion. OH⁻. Step 3: Balance charges. Two OH⁻ ions are needed to balance one Ca²⁺. Chemical formula: Ca(OH)₂.
When should polyatomic ions be bracketed in formulas?
When more than one polyatomic ion is needed in a formula.
How do you name ionic compounds?
The cation is named first. If it has a fixed charge, use the element name. If it has a variable charge, indicate the charge in parentheses. The anion is named with ‘-ide’ if monoatomic, or use its memorized name if polyatomic.
What are some common polyatomic anions and their names?
- OH⁻ = hydroxide
- NO₃⁻ = nitrate
- CO₃²⁻ = carbonate
- SO₄²⁻ = sulfate
What is a covalent substance?
A molecule containing two or more atoms covalently bonded.
What is a monoatomic element?
An element that exists as single atoms.
How are molecules classified by the number of atoms?
- Diatomic: 2 atoms
- Triatomic: 3 atoms
- Polyatomic: More than 3 atoms
What are some common covalent substances and their formulas?
- O₂ = oxygen
- N₂ = nitrogen
- F₂ = fluorine
- Cl₂ = chlorine
- Br₂ = bromine
- I₂ = iodine
- H₂ = hydrogen
- O₃ = ozone
- H₂O = water
- NH₃ = ammonia
- CH₄ = methane
- C₆H₁₂O₆ = glucose
How do you write the chemical formula of carbon dioxide?
Step 1: Identify elements. Carbon (C) and oxygen (O). Step 2: Determine the number of atoms using prefixes: mono (1), di (2), tri (3), tetra (4). One carbon and two oxygen atoms → CO₂.
