Final answer:
The hybridization of [Ni(CN)4]−2 is dsp2, and the bond angles are 90°, corresponding to a square planar geometry.
Step-by-step explanation:
The correct answer to the question 'What is the type of hybridization and bond angle in [Ni(CN)4]−2?' is (b) dsp2, 90°. In this complex, nickel typically forms a square planar geometry which is consistent with dsp2 hybridization. The square planar geometry indicates that the ligands are arranged in the same plane, with 90° angles between them. Unlike the sp3 hybridization which leads to a tetrahedral geometry and 109.5° bond angles, dsp2 hybridization results in a planar molecule with 90° bond angles. This outcome correlates with the characteristics of nickel complexes with strong field ligands such as cyanide (CN−).