What are sources of error in specific heat capacity experiment?

Answer 1

There are many possible causes of errors when doing the experiment on finding the specific heat capacity of specimens. Here are a few facts that caused the errors.

(1)Heat loss: during the experiment while relocating the specimens from the hotplate into the calorimeter took a few seconds and that could be one of the errors.

(2)System error: through the thermometer as well as possibly the inaccurate calibration.

(3)Instrumental error: the calorimeter which had used in this experiment was restored calorimeter which could not be well insulated.

(4)Additional energy: if stirring the water to prevent non-uniform heating, the addition of energy to the water, from the stirring device.

(5)Heat remained: although changing the water from one testing to another testing, the heat still remain in calorimeter and can be understand as residual heat energy inside the calorimeter.

(6)Temperature measurement: time taken is not long enough while the specimen was in the water and reading the temperature.

(7)Human error: reading the thermometer inaccurately and inappropriate uses of apparatus such as placing the calorimeter closely to the hotplate.

Answer 2

There are many possible sources of error, so this answer is superficial.

Firstly there is the question of the sample and the control. It is difficult to get the sample and control strictly comparable. Getting the masses and the states of the sample and control both correct and comparable sometimes is very difficult.

If the sample contains slight impurities, especially impurities of moisture or solvents that could throw readings off badly, and smaller impurities might not throw them off equally badly, but nonetheless introduce errors that are not easily noticed but cause misleading results.

Preparation of the sample that does not fall foul of these problems, none the less might cause chemical changes such as oxidation or physical changes such as recrystallisation or glassy states that bias the readings.

Depending on the nature of the sample, for example, when working with polymers, it can be very difficult to ensure that the cell is properly cleaned between measurements and that the cell is not damaged in any way that affects the results, such as reducing its mass by scratching or wear.

More mundanely, if there is any misunderstanding about the nature of the sample, such that wrong assumptions are made about its behaviour, the significance of the readings and measurements can be totally misunderstood or even nonsensical.