JEE Advanced 2024 — Paper 1 — Question 40

Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. NaOH solution, gives $\mathbf{P}$ and $\mathbf{Q}$. Compound $\mathbf{P}$ does not give Tollen's test, whereas $\mathbf{Q}$ on acidification gives positive Tollen's test. Treatment of $\mathbf{P}$ with excess cyclohexanone in the presence of catalytic amount of p-tolunesulfonic 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 $\qquad$ .