Heat capacity of a calorimeter

Calculate the heat capacity of a calorimeter (Figure 14-1) that, when containing 300 ml of water, requires a current of 0.840 amp passing for 3 min 41 sec through a 9.05 ohm immersed resistance in order to raise the water temperature from 22.376°C to 23.363°C. 

A student needed to calculate the heat capacity of a calorimeter and obtained the following experimental data ... 

Heat calculations must be done differently when the heat capacity of a calorimeter is included. The next Sample Problem illustrates this. 

The heat capacity of a calorimeter, Ccai, is the amount of heat absorbed by the calorimeter per degree Celsius rise in temperature. 

The heat capacity of a calorimeter is determined by adding a known amount of heat and measuring the rise in temperature of the calorimeter and of the solution it contains. This heat capacity of a calorimeter is sometimes called its calorimeter constant. 

Benzoic acid, CgHjCOOH, is often used to determine the heat capacity of a calorimeter. It is a solid that can be compressed into pellets. Its heat of combustion is accurately known ... 

The heat capacity of a gas at constant pressure is nonually detenuined in a flow calorimeter. The temperature rise is detenuined for a known power supplied to a gas flowing at a known rate. For gases at pressures greater than about 5 MPa Magee et al [13] have recently described a twin-bomb adiabatic calorimeter to measure Cy. 

Bomb calorimeter. The heat flow, q, for the reaction is calculated from the temperature change multiplied by the heat capacity of the calorimeter, which is determined in a preliminary experiment... 

WEB When one mole of caffeine (CgHlaN402) is burned in air, 4.96 X 103 kj ofheat is evolved. Five grams of caffeine is burned in a bomb calorimeter. The temperature is observed to increase by 11.37°Q What is die heat capacity of the calorimeter in J/°C ... 

A calorimeter was calibrated with an electric heater, which supplied 22.5 kj of energy to the calorimeter and increased the temperature of the calorimeter and its water bath from 22.45°C to 23.97°C. What is the heat capacity of the calorimeter ... 

A calorimeter is calibrated with an electrical heater. Before the heater is turned on, the calorimeter temperature is 23.6 °C. The addition of 2.02 X 10 J of electrical energy from the heater raises the temperature to 27.6 °C. Determine the total heat capacity of this calorimeter. 

C06-0015. When 10.00 mL of 1.00 M HCl solution is mixed with 115 mL of 0.100 M NaOH solution in a constant-pressure calorimeter, the temperature rises from 22.45 °C to 23.25 °C. Assuming that the heat capacity of the calorimeter is the same as that of 125 g of water, calculate q for this reaction. 

C06-0017.A coffee-cup calorimeter is calibrated using a small electrical heater. The addition of 3.45 kJ of electrical energy raises the calorimeter temperature from 21.65 °C to 28.25 °C. Calculate the heat capacity of the calorimeter. 

It must be noted that the heat capacity of the calorimeter cell and of its contents p, which appears in the second term of Tian s equation [Eq. (12)], disappears from the final expression giving the total heat [Eq. (19)]. This simply means that all the heat produced in the calorimeter cell must eventually be evacuated to the heat sink, whatever the heat capacity of the inner cell may be. Changes of the heat capacity of the inner cell or of its contents influence the shape of the thermogram but not the area limited by the thermogram. It is for this reason that heat-flow microcalorimeters, with a high sensitivity, are particularly convenient for investigating adsorption processes at the surface of poor heat-conducting solids similar in this respect to most industrial catalysts. 

The overall heat capacity of the calorimeter is a simple function of the amount of steel the bomb comprises and the amount of water surrounding it. If the mass is m and the heat capacity is C, then the overall heat capacity is expressed by... 

Some of the heat transferred to the surroundings during an exothermic reaction are absorbed by the calorimeter and its parts. In order to account for this heat, a calorimeter constant or heat capacity of the calorimeter is required and usually expressed in J °C 1. 

Scenario A student constructed a coffee cup calorimeter (see Figure 1). To determine the heat capacity of the calorimeter, the student placed 50.0 mL of room temperature distilled water in the calorimeter. A calibrated temperature probe recorded the temperature as 23.0°C. The student then added 50.0 mL of warm distilled water (61.0°C) to the calorimeter and recorded the temperature every 30 seconds for the next three minutes. The calorimeter was then emptied and dried. Next, the student measured the temperature change when 50.0 mL of... 

We ignited a 1.5886 g sample of glucose (C6H1206) in a bomb calorimeter. The temperature increased by 3.682°C. The heat capacity of the calorimeter was 3.562 kJ/°C, and the calorimeter contained 1.000 kg of water. Find the molar heat of reaction (J/mol of glucose) for the reaction ... 

Some problems use the total heat capacity of the calorimeter (calorimeter + water). This means that the summation has already been done for you, so that you do not need to do the summation a second time. 

After the temperature change is calculated, there are several ways to proceed. If the calorimeter contains water, the heat may be calculated by multiplying the specific heat of water by the mass of water by the temperature change. The heat capacity of the calorimeter may be calculated by dividing the heat by the temperature change. If a reaction is carried out in the same calorimeter, the heat from that reaction is the difference between the heat with and without a reaction. 

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