The gas given off when ethanol reacts with sodium is

Analyze the question: It asks which gas is released when ethanol (an alcohol) reacts with sodium metal.

Concept: Alcohols contain the hydroxyl group (-OH). Like water, the O-H bond can be broken by a reactive metal such as sodium. The sodium replaces the hydrogen of the -OH group, forming a sodium alkoxide and releasing hydrogen gas.

Solution:

Equation:

2C₂H₅OH + 2Na → 2C₂H₅ONa + H₂↑

• Ethanol: C₂H₅OH
• Sodium ethoxide: C₂H₅ONa (the product)
• Gas evolved: H₂

This is similar to sodium reacting with water: 2H₂O + 2Na → 2NaOH + H₂. The reaction with ethanol is just gentler.

Checking the other options:

• A. Carbon(IV) oxide: produced when ethanol burns completely or when carbonates react with acids, not here.
• C. Methane: not formed, because no C-C or C-H bonds are broken.
• D. Oxygen: sodium is not an oxidizing agent. It takes oxygen's bonding partner, it does not release oxygen.

Answer: B. Hydrogen

Tip: Remember "Na + OH-containing compound → H₂ gas." This applies to water, alcohols, and acids. A common test for the -OH group in alcohols is that sodium gives effervescence of hydrogen, which burns with a "pop" sound when a lit splint is brought near.