question_answer 71)

  Which of the following statements are correct about \[CO_{3}^{2-}\]? (a) The hybridisation of central atom is \[s{{p}^{3}}\] (b) Its resonance structure has one C-O single bond and two C = O double bonds (c) The average formal charge on each oxygen atom is -0.67 units (d) All C-O bond lengths are equal

Answer:

  (c, d) In\[CO_{3}^{2-}\], the hybridisation of carbon atom is \[s{{p}^{2}}\] and not\[s{{p}^{3}}\]. Its resonance structure is : i.e., the resonance structure has two C - O bonds and one C = O bond. Formal charge on double bond oxygen = 0 Formal charge on single bonded oxygen = -1 Average formal charge on oxygen = \[\frac{0-1-1}{3}=-\frac{2}{3}\] = - 0.67 All C - O bond lengths are same.