Which bond from each set is the longest n-o or n=o

N-O is longer

Explanation:

Length of a covalent bond decreases with increase in electron density between two bonded atoms. Because increase in electron density produces more negative charge density between two bonded atoms. Hence this negative charge density strongly attract positively charged bonded nucleus towards itself.Electron density in a covalent bond increases if there exists pi bond along with a sigma bond. Higher the number of pi bonds, higher will be electron density.Therefore bond in N=O is more electron dense. Hence N=O bond is shorter and N-O is longer.

Work done = force ×distancebut force = mass ×gravityand gravity = 10m\s force = 2×10 = 20 work done = 20×3 = 60 joules