Mischievous students are often eager to start Chemistry class with dreams of creating explosives, mixing up deadly poisons, or dissolving things in corrosive acid. Much to the surprise and harm of many people every year, the typical household already possesses more than enough ingredients for havoc. This is all-too-often discovered by mistake and too late to avoid serious damage, injury, or even death. Take a practical lesson in chemistry right now and note these common household items that should not be combined.

1. Bleach + Vinegar = Deadly Chlorine Gas
Bleach is the common name for sodium hypochlorite. Vinegar is a diluted (typically to 5%) form of acetic acid. While each work well as cleaners and disinfectants, when they are combined, the acid releases chlorine gas and chloramine vapors. These byproducts cause nasty chemical burns — particularly in the eyes and the lungs.

2. Bleach + Ammonia = Toxic and Explosive Gases
The combination of these two cleaning agents releases chloramine vapor, with a potential for hydrazine formation. Inhaling the vapors plays havoc with one’s respiratory system with burns and scarring. Liquid hydrazine is unstable and explosive. (See this story about a man who died mixing ammonia, bleach, and Drano to clean his toilet)

Be sure to check the ingredients lists of your cleaning products to ensure you’re not unknowingly using these products together. For instance, Windex comes in both ammonia and ammonia-free formulas. Certain formulations of Drano contain bleach.

3. Rubbing Alcohol + Bleach = Chloroform
Bleach contains sodium hypochlorite, which reacts with ethanol or isopropyl alcohol to produce chloroform, hydrochloric acid, and other compounds, such as chloroacetone or dichloroacetone.

These chemicals combined or individually damage the nervous system, eyes, lungs, skin, liver, and kidneys. High levels of chloroform exposure may result in death, while lower levels could result in dizziness and nausea.

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