All the substances listed below are fertilizers that contribute nitrogen to the soil. Which of these is the richest source of nitrogen on a mass percentage basis ?

% composition = At.wt of element ×Number of atoms of the element per molecule ×100Molecular weight1). = 2×14×10060 =46.662). = 2×14×10080 = 353). = 1×14×10030 = 46.664). = 1×14×10017 = 82.35