1000 Questions Ionisation energies

Ionisation Energy

  1. Explain why helium’s first ionisation energy is the highest first ionisation energy. Answer

 

  1. Explain why lithium has lower ionisation energy than helium even though lithium has 1 proton more. Answer

 

  1. Explain the trend in ionisation energy across a period. Answer

 

  1. Explain why the ionisation energy of a group III atom is lower than that of group II. Answer

 

  1. Explain why the first ionisation of magnesium is 736 kJ mol-1whilst that of beryllium is 900 kJ mol-1. Answer

 

  1. Which is higher: the second ionisation energy of sodium or the second ionisation energy of magnesium. Explain. Answer

 

  1. The four successive ionisation energies of beryllium are: 900 1760 14800 21000 (kJ mol-1). Show why beryllium is classified as a group II element. Answer

 

  1. Give the group number for the following elements having these successive first ionisation energies. Answer
    1. 799 2420 3660 25040 32850
    2. 1000 2260 3390 4540 6990 8790 27100 31700
    3. 736 1450 3740 7740 18000 21700 25600 29400

 

  1. Which would have a greater value for the second ionisation energy: magnesium or aluminium? Answer

 

  1. Which would have a greater value for the third ionisation energy: magnesium or aluminium? Answer

Answer Worksheet