Question

The grid below represents part of the periodic table. Study it and answer the questions that follow. The letters are not actual symbols of the elements.

1. What name is given to the family of elements to which A and C belong? 
2. Write the formula of the sulphate of element D. 
3. Which letter represents the most reactive; 
   1. Metal
   2. Non-metal
4. Name the bond formed when B and H react. Explain your answer. 
5. Select one element that belongs to period 4. 
6. Explain why the ionic radius of element E is bigger than the atomic radius. 
7. The electron configuration of a divalent anion of element N is 2.8.8. Indicate the position of element N on the periodic table above. 
8. The oxide of G has a lower melting point than the oxide of L. Explain. 
9. How do the atomic radii of I and C compare. Explain. 
10. Explain the trend in the 1st ionization energies of the elements J, I and L.

Answer 1

1. Noble gases
2. D₂SO₄
3.   
   1. D
   2. E
4. Ionic bond. It involves transfer of electrons from B to H.
5. D
6. During ionization, an extra electron is added to the energy shell which reduces the effective nuclear force of attraction.
7. Placed in group VI and period 3.
8. G forms a simple molecular structure with oxygen while L forms a giant atomic (covalent) structure with strong covalent bonds which require more heat to break.
9. I is larger than C. I has a lower effective nuclear charge due to smaller number of protons hence weaker attraction between the outermost energy level and the nucleus.
10. It increases across from J to L due to increase in the effective nuclear charge from J to L.