relative mass

• What is the relative atomic mass based on?

  A twelfth of the mass of a carbon atom
• Why do different elements have different masses?

  They have different numbers of protons and neutrons
• What is the mass of a hydrogen atom compared to a uranium atom?

  Hydrogen has a very small mass
• What is the relative atomic mass of carbon?

  12
• How is the relative atomic mass of other elements determined?

  Relative to a twelfth of carbon's mass
• What are the relative atomic masses of nitrogen, oxygen, and hydrogen?

  Nitrogen is 14, oxygen is 16, hydrogen is 1
• Why aren't atomic masses whole numbers?

  Because elements have isotopes with different neutrons
• What is the relative atomic mass of magnesium?

  24.3
• Where can you find the relative atomic mass on the periodic table?

  It is the big number
• What is the atomic number also known as?

  The proton number
• To how many decimal places will calculations be done?

  One decimal place
• What is the relative molecular mass of a water molecule?

  18
• What is the formula for ethanol and its relative molecular mass?

  C₂H₆O, mass is 46
• How do you calculate the relative formula mass of sodium chloride (NaCl)?

  Add 23 and 35.5 to get 58.5
• What are the definitions of relative atomic mass, relative molecular mass, and relative formula mass?

  • Relative atomic mass: Mass of an element compared to a twelfth of carbon's mass.
  • Relative molecular mass: Mass of a molecule.
  • Relative formula mass: Mass of ionic compounds.
• What is the relative atomic mass of oxygen?

  16
• What is the relative atomic mass of fluorine?

  19
• What is the relative atomic mass of neon?

  20
• What is the significance of isotopes in determining atomic mass?

  They cause variations in atomic mass values
• How does the concept of relative atomic mass differ from relative molecular mass?

  Relative atomic mass is for elements, molecular mass is for molecules