Final answer:
The order of bond polarity from least to most polar is CH, NH, NO, CO, based on the differences in electronegativity between the bonded atoms, with CO being the most polar due to the high electronegativity of oxygen.
Step-by-step explanation:
The order of polarity of the given bonds CO, NO, CH, NH can be determined by looking at the electronegativity differences between the bonded atoms. A larger difference in electronegativity values indicates a more polar bond. Since oxygen and nitrogen are more electronegative than carbon and hydrogen, the bonds with oxygen and nitrogen will generally be more polar.
Here is the order of polarity from least to most polar:
CH < NH < NO < CO
Carbon and hydrogen have a smaller difference in electronegativity, making CH the least polar. NH is more polar than CH due to nitrogen being more electronegative than carbon. NO is more polar than NH due to the same reason. Finally, CO is the most polar because oxygen is more electronegative than both carbon and nitrogen.