Solution:
Option (i) and (iv) are the answers.
Group 13 elements create electron-deficient compounds and are thus Lewis acids. Electron-rich hydrides have lone pairs of extra electrons. Compounds of elements 15-17 exist. So they are Lewis bases.
Which of the following statements is correct? (i) Hydrides of group 13 act as Lewis acids. (ii) Hydrides of group 14 are electron deficient hydrides. (iii) Hydrides of group 14 act as Lewis acids. (iv) Hydrides of group 15 act as Lewis bases.