Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. $\mathrm{NaOH}$ solution, gives $\mathbf{P}$ and $\mathbf{Q}$. Compound $\mathbf{P}$ does not give Tollens' test, whereas $\mathbf{Q}$ on acidification gives positive Tollens' test. Treatment of $\mathbf{P}$ with excess cyclohexanone in the presence of catalytic amount of $p$-toluenesulfonic acid (PTSA) gives product $\mathbf{R}$.

Sum of the number of methylene groups $\left(-\mathrm{CH}_2-\right)$ and oxygen atoms in $\mathbf{R}$ is __________.

In the reaction given below, the total number of atoms having sp² hybridization in the major product P is _________.

In the following reaction, compound Q is obtained from compound P via an ionic intermediate



What is the degree of unsaturation of Q?

In the following reaction sequence, the amount of $$D$$ (in g) formed from $$10$$ moles of acetophenone is ___________.

(Atomic weights in $$g\,mo{l^{ - 1}}:H = 1,C = 12,$$ $$N = 14,O = 16,$$ $$Br = 80.$$. The yield (%) corresponding to the product in each step is given in the parenthesis)