What is the risk of mixing hydrogen peroxide with bleach?

• A. It creates a potentially deadly gas
• B. It smells pleasant
• C. It becomes harmless water
• D. It neutralizes the bleach

Answer: (A)

Mixing hydrogen peroxide with bleach releases chlorine gas, a toxic substance. Both cleaners are strong oxidizers, and when combined the peroxide drives a reaction with the hypochlorite in bleach to form chlorine gas. Inhaling chlorine gas can irritate or damage the lungs and airways, causing coughing, shortness of breath, chest pain, and potentially life-threatening problems in concentrated exposures. For safety, never mix these cleaners; use them separately and ensure good ventilation. If exposure occurs, move to fresh air and seek medical help if symptoms develop. The other options aren’t correct because the mixture does not produce a pleasant smell, turn into harmless water, or neutralize the bleach.