Elements,isotops and relative atomic mass

• What is an atom made up of?

  A central nucleus and orbiting electrons
• What determines the identity of an element?

  The number of protons in its nucleus
• What is the smallest element?

  Hydrogen
• How many protons does a hydrogen atom have?

  One proton
• What do the boxes in the periodic table represent?

  Different elements
• What is the atomic number?

  The number of protons in an atom
• What are isotopes?

  Elements that have the same number of protons but different amount of neutrons.
• What do isotopes have in common?

  The same number of protons
• How do isotopes react chemically?


  They react in basically the same way
• What is relative atomic mass?

  The average mass of all isotopes of an element
• What does abundance mean in the context of isotopes?

  How common or rare an isotope is
• What is the equation for relative atomic mass?

  Sum of isotope abundance times mass divided by total abundance
• What is the first step in calculating relative atomic mass for copper?

  Multiply each isotope's abundance by its mass
• What is the final calculation for relative atomic mass of copper?

  Divide total by 100
• What is the relative atomic mass of copper rounded to one decimal place?

  63.6
• What symbol denotes relative atomic mass?

  Ar
• What does the average mass of a copper atom represent?

  The relative atomic mass of copper
• What are isotopes and how do they differ?

  • Isotopes are forms of the same element
  • Same number of protons, different number of neutrons
  • They have different masses but similar chemical properties
• How do you calculate the average mass of isotopes for an element?

  1. Multiply each isotope's abundance by its mass
  2. Sum these values
  3. Divide by the total abundance of isotopes