Why does hydrogen peroxide bubble?
Show answer & explanation
Answer: Decomposes releasing oxygen
Boils at room temperature — Wrong. Hydrogen peroxide doesn't boil at room temp. Bubbling comes from decomposition into water and oxygen gas when contacting catalysts.
Decomposes releasing oxygen ✓ — Correct! Hydrogen peroxide (H₂O₂) is unstable, slowly decomposing: 2H₂O₂ → 2H₂O + O₂. When applied to wounds, enzyme catalase (in blood/cells) rapidly catalyzes this reaction, releasing oxygen gas—bubbles! This also helps clean wounds (lifts debris). Brown bottles slow decomposition (light-sensitive). Pure H₂O₂ is dangerous—store-bought is 3% solution!
Mixes with air molecules — Wrong. Bubbles aren't from air mixing. H₂O₂ decomposes chemically (accelerated by enzymes) releasing oxygen gas as product.