Chemical Formulas

• What is ionic bonding?

  A type of chemical bonding where atoms transfer electrons
• What can common ions form when atoms lose or gain electrons?

  They can form positive or negative ions
• How can you predict the charge of some ions?

  By their position in the periodic table
• What is the charge of a lithium ion?

  Li⁺
• What is the charge of a magnesium ion?

  Mg²⁺
• What is the charge of a chloride ion?

  Cl^-
• What is the formula for the carbonate ion?

  CO₃^2-
• What do positive ions combine with to form ionic compounds?

  Negative ions
• What is the overall charge of any ionic compound?

  The overall charge is zero
• How do you determine the formula of an ionic compound?

  By balancing the positive and negative charges
• What is the chemical formula of calcium nitrate?

  Ca(NO₃)₂
• What prefix indicates one atom in a molecule?

  Mono
• What is the chemical formula for water?

  H₂O
• What is the chemical formula for ammonia?

  NH₃
• What is the chemical formula for oxygen?

  O₂
• What is the chemical formula for carbon dioxide?

  CO₂
• Why is it important to learn chemical formulas for common molecules?

  They frequently appear in exams and practical applications
• What is the chemical formula of magnesium hydroxide?

  Mg(OH)₂
• What are the common positive ions and their charges?

  • Lithium: Li⁺
  • Sodium: Na⁺
  • Potassium: K⁺
  • Magnesium: Mg²⁺
  • Calcium: Ca²⁺
  • Aluminium: Al³⁺
• What is the process to write the formula of an ionic compound?

  1. Identify the positive and negative ions.
  2. Ensure the total charge is zero.
  3. Use the charges to balance the ions.
  4. Write the formula using chemical symbols.
• What are the prefixes used in chemical formulas and their meanings?

  • Mono = one
  • Di = two
  • Tri = three
• What are some common molecules and their formulas?

  • Water: H₂O
  • Hydrogen: H₂
  • Ammonia: NH₃
  • Chlorine: Cl₂
  • Carbon dioxide: CO₂
  • Oxygen: O₂