Chemicals Used in a Cold Pack

Cold packs are instant aids that help reduce the swelling and inflammation that come from common injuries such as sprains or muscle pulls. They are convenient replacements for crushed ice bags. Athletes often use cold packs to treat an injury. Certain chemicals in a cold pack make this device work properly when someone applies it to an injury.

Ammonium Nitrate

• Ammonium nitrate is a chemical compound added in cold packs along with water. Keep the two separate until someone strikes or breaks the cold pack. When this happens, ammonium nitrate and water mix. The mixture creates an endothermic reaction and absorbs heat, but the temperature begins to fall soon after.

Ammonium Chloride

• Ammonium chloride is another chemical you will find in cold packs. When ammonium chloride dissolves in water, it causes the surroundings to get cold. Therefore, when ammonium chloride mixes with water inside a cold pack, the bag gets cold and the temperature drops in solution. A person can feel the cold energy from the pack when someone applies it to the skin.

Rubbing Alcohol

• According to Education.com, you can make a homemade cold pack by using a plastic freezer bag, water and rubbing alcohol. Add water and the rubbing alcohol in a bag in a 2:1 ratio. Double bag it to prevent leaking. Put the bag in a freezer and wait for the water to freeze. The water freezes, but the rubbing alcohol will not. Take the cold pack out and apply the liquid portion on the sprained or injured area so that it conforms to the shape of the body part.