Which calorimeter is more accurate?

bomb calorimeterA bomb calorimeter is more accurate than a simple calorimeter.

Why is the calorimeter so accurate?

For example, when an exothermic reaction occurs in solution in a calorimeter, the heat produced by the reaction is absorbed by the solution, which increases its temperature. … This enables the accurate determination of the heat involved in chemical processes, the energy content of foods, and so on.

Why is a calorimeter not accurate?

Limitations of Calorimetry

Although bomb calorimeters in laboratories have insulation to minimize these loses, it’s impossible to stop all heat loss. Moreover, the reactants in the calorimeter may not be well-mixed, which leads to uneven heating and another possible source of error in your measurements.

Are calorimeters accurate?

Accuracy of the instrument was based on ≤1.5% percent relative error from theoretical values, i.e. Respiratory Exchange Ratio (RER) = 0.667, and % Gas recovery = 100%. Table 1 shows the accuracy of the 12 indirect calorimeters tested and the instrument rankings based on % relative error from theoretical values.

How do you calibrate a calorimeter?

The calibration is accomplished using a reaction with a known q, such as a measured quantity of benzoic acid ignited by a spark from a nickel fuse wire that is weighed before and after the reaction. The temperature change produced by the known reaction is used to determine the heat capacity of the calorimeter.

How is a bomb calorimeter more accurate?

Comparatively, the bomb calorimeter calculates every aspect of the initialization, firing and final phase of the determination, continuously comparing the results against the calibration curve, providing a compensated result accurate to four decimal places.

Why do you need to calibrate a calorimeter?

You calibrate the calorimeter to get its heat capacity. So when the reaction raises the temperature of the calorimeter, you can multiply the change in temperature with the heat capacity to get heat of the calorimeter, which in turn will give you the heat released by the reaction.

Is indirect calorimetry accurate?

Indirect calorimetry (IC) provides one of the most sensitive, accurate, and noninvasive measurements of EE in an individual. Over the last couple of decades, this technique has been applied to clinical circumstances such as acute illness and parenteral nutrition.

Which of the following limitations are most likely to impact the accuracy of indirect calorimetry measurements?

The major limitations are the equipment size and poor portability. Closed-circuits could lead to reduction of alveolar ventilation due to increased compressibility of the breathing circuit and may result in increased work of breathing (21, 22).

Why is the calorimeter usually calibrated with water?

Calibrating the calorimeter takes its heat loss into effect, so that only the temperature of the sample can be determined.

What does the calibration curve of a calorimeter tell you?

The calibration curve is a plot of how the instrumental response, the so-called analytical signal, changes with the concentration of the analyte (the substance to be measured). … The operator can measure the response of the unknown and, using the calibration curve, can interpolate to find the concentration of analyte.

Why does a calorimeter need to be insulated?

A calorimeter uses an insulated lid, or insulated surroundings. … The goal of insulating the bomb calorimeter system is to minimize the temperature loss from the system (calorimeter) to the surroundings (air) over time.

Can other liquids besides water be used in a calorimeter?

It is derived from the Latin word “calore” meaning “heat.” Water is best to use in a calorimeter because it has a high specific heat, however, other liquids such as ethanol can also be used.

What is a calorimeter experiment?

A calorimeter is a device used to determine heat flow during a chemical or physical change. … In this experiment you will heat a known mass of a metal to a known temperature and then transfer it to a calorimeter that contains a known amount of room temperature water (Tc).

Why is the calibration of the coffee cup calorimeter?

A coffee cup is a good insulator so, most of the heat should go only into the water, and not much into the coffee cup. But to be sure, we will calibrate the calorimeter so we know exactly how much heat it absorbs.

How do you use a calorimeter?

Does the amount of water in a calorimeter matter?

The calorimeter exists as a fixed unit, thus its heat capacity is a fixed value. The amount of water in the calorimeter, however, can vary, and thus the heat capacity of the water can vary. When dealing with variable amounts of material, one often prefers to use an intensive measure of the heat capacity.

How much heat was absorbed by the calorimeter?

The heat absorbed by the calorimeter is q1 = 534 J/°C × (26.9 °C – 23.4 °C) = 1869 J. The heat absorbed by water is q1 = 675 mL × 0.997 g/mL × 4.184 J/g °C × (26.9 °C – 23.4 °C) = 9855 J. The overall amount of heat q = q1 + q1 = 11,724 J or 11.7 kJ with three significant digits.

How do you set up a calorimeter in a lab?

How do you do a calorimeter laboratory?

To use the calorimeter, the inner cup is half filled with a known mass of water, and the temperature is measured. The sample is added, the temperature is measured again, and the desired quantity (latent heat or specific heat) is calculated.

Does a calorimeter absorb heat?

Ideally, the components of the calorimeter would absorb no heat, but the components of the calorimeters always absorb some energy from the system. The heat capacity of the calorimeter is the quantity of heat absorbed by the calorimeter for each 1°C rise in temperature.

Does a calorimeter release heat?

A calorimeter is a device used to measure the amount of heat involved in a chemical or physical process. For example, when an exothermic reaction occurs in solution in a calorimeter, the heat produced by the reaction is absorbed by the solution, which increases its temperature.