Back in 1950s, it was common to have as house cleaning items bleaching solution (containing sodium hypochlorite) and ammonia (used to remove, for example, hair dye stains). However, many people ended up in hospital after using them both, why?

Hypochlorite reacts with ammonia to yield chloramine and water. (emphasise to the students that hypochlorite is an oxidising agent, getting reduced to chloride ions). chloramine is a very toxic gas, since it attacks the proteins in our bodies, at their amino groups. It is a perfect alkylating agent, destroying any reactive nucleophiles it meets along the way.Take home question: How would you safely get rid of spilled hypochlorite? (Answer: think of a reducing substance, so that both the reactant and the products are not poisonous; for example: thiosulphate