Multiple choice Which of the following pairs of species have the same bond order? O2-- NO+ CN- CO 1 and 2 1 and 4 1, 2 and 3 1, 3 and 4 2, 3 and 4 Reveal answer Fill a bubble to check yourself E Correct answer Explanation Species which have the same number of total electrons will have the same bond order. O2-- has 18 electrons and bond order 1. NO+, CN-, and CO each has 14 electrons having bond order 3.