A small piece of sodium is added to methanol in a dry test tube. The metal fizzes and slowly disappears as a gas is given off. Which gas is released in this...
Question 1 Report
A small piece of sodium is added to methanol in a dry test tube. The metal fizzes and slowly disappears as a gas is given off. Which gas is released in this reaction?
Answer Details
Methanol contains the \( \mathrm{-OH} \) group shown at the right of the structure, and sodium is reactive enough to displace the hydrogen atom bonded to that oxygen. The metal fizzes as hydrogen is released and dissolves as sodium methoxide forms:
\[ \mathrm{2CH_3OH + 2Na \rightarrow 2CH_3ONa + H_2} \]
This is the same type of reaction as sodium with water, but gentler, because an alcohol gives up its \( \mathrm{-OH} \) hydrogen less readily. You would confirm the gas with a lighted splint, which produces a squeaky pop. No chlorine is present anywhere in the reactants, and the oxygen stays bonded within the methoxide, so neither can be given off. Carbon dioxide would require the carbon to be oxidised, which needs burning, not a metal.
Download The App On Google Playstore
Everything you need to excel in your exams
