Boron and its Compounds — Prelims Questions

Which of the following statements about boric acid ($H_3BO_3$) is incorrect?

Which of the following compounds contains 3-center 2-electron bonds?

When borax is heated strongly, it forms a transparent glassy bead. This bead consists of:

Which of the following statements correctly describes the trend in Lewis acidity for boron trihalides ($BX_3$)?

Which of the following reactions correctly represents the preparation of diborane ($B_2H_6$) in the laboratory?

Which of the following is an incorrect statement regarding the properties of boron?