Question

The coordination number of Cr in [Cr(NH₃)₃(H₂O)₃]Cl₃ is ___________.

Options

• 6

• 3

• 4

• 2

Answer 1

The coordination number of Cr in [Cr(NH₃)₃(H₂O)₃]Cl₃ is 6.

Explanation:

The coordination number of the central metal atom/ion is equal to the number of neutral molecules or negative ions bound to the central metal atom/ion by non-ionizable secondary linkages. These neutral molecules or negative ions are the ones that are shown inside the square bracket. Here there are 3NH₃ molecules and 3H₂O molecules associated with Cr inside the bracket. So the coordination number of Cr is 6.