preview

Cold Pack Lab Report

Decent Essays

The purpose of this lab investigation is to determine which salt and at what quantity will produce the most effective and economical instant cold pack. A cold pack consists of two compartments, one containing water and the other containing a salt. Squeezing the cold pack gives off heat and breaks the barrier, allowing for the salt to dissolve in water and drop to 2°C. Many people use cold packs to reduce swelling and decrease blood flow of an injured area. Furthermore, cold packs absorb heat from their surroundings, making them endothermic systems that decrease/cool the temperature of their surroundings. Recording temperature changes and enthalpies of each ionic compound are needed to conclude which salt will produce the most effective cold pack. …show more content…

Heat or q of water is determined by the formula q = m x s x ∆ T, and q of the solution is q solution = - q water. In order to calculate ∆H, a calorimeter, an isolated system is used to calculate the heat of a chemical reaction. Using the heat found by the calorimeter, heat (kJ) is divided by the number of moles (n) in order to calculate ∆H of a solution. Enthalpy is used to determine if a system is endothermic or exothermic. If the ∆H of a system is negative then the system will be exothermic. If the ∆H of a system is positive then the system will be endothermic. The salt that yields the highest ∆H with the lowest cost per unit of grams needed to drop to 2 °C, will be the most effective and economical ionic compound to make the best cold

Get Access