atomic and mass numbers

• What is the central part of an atom called?

  Nucleus
• What particles are found in the nucleus of an atom?

  Protons and neutrons
• What charge do protons have?

  Positive charge
• What charge do neutrons have?

  No charge
• What charge do electrons have?

  Negative charge
• What is the atomic number?

  Number of protons in an atom
• How many protons does a sodium atom have?

  11 protons
• Why do all sodium atoms have 11 protons?

  It defines the element sodium
• Why do atoms have no overall charge?

  Electrons equal the number of protons
• How many electrons does a sodium atom have?

  11 electrons
• What is the mass number?

  Total number of protons and neutrons
• How do you calculate the number of neutrons in sodium?

  Mass number minus atomic number
• What is the number of neutrons in sodium?

  12 neutrons
• What are isotopes?

  Atoms with the same protons but different neutrons
• How many neutrons does the left isotope of sodium have?

  12 neutrons
• How many neutrons does the right isotope of sodium have?

  13 neutrons
• What happens when a sodium atom loses one electron?

  It becomes a sodium ion with +1 charge
• What is a sodium ion?

  A sodium atom with a +1 charge
• What charge does an atom have if it loses two electrons?

  +2 charge