Lab 2: Determine Specific Heat of Substance
Sѐnchez Blades, Kayla Meeks, and George Colon-Pena, Tanardjah Washington
Date: July 1, 2015
Tanardjah Washington July 6, 2015 Chemistry 1211 L Dr. Song
The study of measuring the heat change of certain chemical reactions or physical changes is known as calorimetry (Laidler, 1995). A commonly used calorimeter in labs is the “coffee-cup” calorimeter made of Styrofoam (Petrucci, et al., 2010). This device is not a closed system (not pressure-tight) and therefore the outer pressure is equal to the internal pressure. This knowledge would allow one to calculate certain information using [mass x specific heat x temperature]. This can be used because when both the internal and external pressures are equal, the heat of the reaction is equal to the enthalpy change of the reaction (Petrucci, et al., 2010).It is also known that the heat of the calorimeter is equal to the negative of the heat of the system.
Specific heat is defined as the amount of heat required to raise the temperature of a single gram of that substance by one degree Centigrade (Petrucci, et al., 2010). This is commonly heard of as a calorie. Every substance will have its own heat capacity, and it is assumed that the solution’s heat capacity is the same as water, 4.184 J/gC.
As mentioned, calorimetry is used to determine the heat of a reaction, but more specifically, the heat of a neutralization reaction (Petrucci, et al., 2010). A neutralization reaction involves the formation of a water molecule (as to neutralize the reaction). The formation of these molecules, from either hydrogen (hydronium) or hydroxide ions, results in the heat of the reaction (q) (Petrucci, et al., 2010). Both strong electrolytes (such as a hydrochloric acid and sodium hydroxide solution) and weak electrolytes (such as phenol and a...