Many chemicals are so strong that they can quickly burn the skin. All chemicals should always be stored away from children. Some common acids include tile cleaner, swimming pool acids, and acid inside car batteries.
Muriatic acid is especially strong.
Cement, dry or wet. Strong oxidizers, such as chlorine. First aid for skin exposure to a caustic chemical is simple. Rinse it off with running water. Continue rinsing for a minimum of 15 minutes.