interpreting chem formulas

• Chemical formula tells us the elements in a molecule and the numbers of atoms of each element
• In the compound hydrogen fluoride:

  • 1 atom of hydrogen
  • 1 atom of fluorine
• In the compound potassium iodide:

  • 1 atom of potassium
  • 1 atom of iodine
• In the compound calcium sulfate:

  • 1 atom of calcium
  • 1 atom of sulfur
  • 4 atoms of oxygen
• In a specific compound, the number of atoms of each element is fixed
• In the compound calcium sulfate, changing the number of atoms results in a different compound, calcium sulfite
• In the compound magnesium hydroxide:

  • 1 atom of magnesium
  • 2 atoms of oxygen
  • 2 atoms of hydrogen
• In compound identification:

  • Copper iodide: 1 atom of copper, 1 atom of iodine
  • Iron bromide: 1 atom of iron, 2 atoms of bromine
  • Zinc carbonate: 1 atom of zinc, 1 atom of carbon, 3 atoms of oxygen
  • Aluminum hydroxide: 1 atom of aluminum, 3 atoms of oxygen, 3 atoms of hydrogen