A Bomb calorimeter is a constant-volume calorimeter used to measure the heat of combustion of the enclosed chemical reaction. It consist consists of a chamber of a chamber that is air and water tight, with a gadget that allows the introduction of high pressure O2 gas and administration of current through a wire (1). A known quantity of a substance is compressed into a pellet, and it wrapped with a conductor wire was then placed into the bomb body (1). Oxygen gas was pumped into the chamber to a pressure of 12 atmospheres; the bomb was submerged into 2-L of deionized water, with a thermometer measuring water temperature; and then an electrical charge was sent through the conductor wire (1).
The experimental measureable in this reaction is the heat flow under constant volume conditions. From the first law of thermodymamic, the heat of reaction is related to the change in internal energy and is shown by:…show more content… q is the heat absorbed or produced and w is the work done on or by the system. The system is at constant volume and does not undergo expansion work.
ΔU = qv (5.5.4)
To determination of the heat of combustion of the system at constant volume and is related to the specific heat capacity, cv, of the system and the temperature change. The heat of combustion of the bomb calorimeter can be obtained: qsystem = Cv x ΔT
The measured heat flow in the bomb is equal to the change in internal energy for the reaction. Since the object is to determine the enthalpy of the reaction, ∆H, is equal to the heat transferred to the system at constant pressure (P) and moles (V).
ΔH = ΔU + Δ(PV) (5.5.5)
Benzoic acid will be used as a means of obtaining the heat capacity of the calorimeter.
C6H5COOH (S) + 15/2 O2 (g) → 7CO2(g) + 3H2O(l)
The purpose of this experiment is to determine the heat of combustion of naphthalene. The combustion reaction