4. The atomic numbers of elements, U, V, W and X are 13, 14, 16 and 17 respectively. Which one of the elements will react with oxygen to form an ionic compound? (Atomic number of oxygen is 8) X A. B. V C. W D. U 5. A. B. X C. Y D. The atomic numbers of elements W, X, Y and Z are 12, 13, 15 and 19 respectively. Thich one of the elements reacts most readily with cold water W 6. A. Z The atomic numbers of elements X and Y are 12 and 9 respectively. Which one of the following is a property of a compound formed between X and Y? It conducts electricity B. It is soluble in organic solvent C. It is a solid of low melting point D. It has a giant molecular structure