In Liebig's combustion method for estimating carbon and hydrogen, the correct sequence of U-tubes us — Practical Organic Chemistry and Purification Chemistry Question

💡 Solution & Explanation

The anhydrous $CaCl_2$ tube must come first to absorb $H_2O$ vapor. If $KOH$ is placed first, it will absorb both $H_2O$ and $CO_2$, ruining the estimation.