A sample of ammonium cyanate (\( \text{NH}_4\text{CNO} \)) undergoes complete thermal rearrangement to form urea (\( \text{NH}_2\text{CONH}_2 \)). If 1 mole of urea is produced, what is the ratio of total covalent bonds in the urea product to that in the reactant cyanate ion (\( \text{CNO}^- \)), assuming urea has standard single and double bonds?

In urea, \( \text{O}=\text{C}(\text{NH}_2)_2 \), there are 4 \( \text{N}-\text{H} \) single bonds, 2 \( \text{C}-\text{N} \) single bonds, and 1 \( \text{C}=\text{O} \) double bond (consisting of 1 \( \sigma \) and 1 \( \pi \), total 2 shared electron pairs / bonds), giving 7 total covalent bonds (8 shared pairs if counting double bond as 2 bonds; total chemical bonds = 7: 4 N-H, 2 C-N, 1 C=O bond). In cyanate ion [N=C=O]⁻ or [N≡C-O]⁻, total number of shared bonds is 3. Hence, the ratio is 7 : 3.