Final answer:
Experimental errors affect the calculation of kilocalories per gram in calorimetry by either underestimating or overestimating the actual energy content, yielding either higher or lower values than the true content.
Step-by-step explanation:
Experimental errors can significantly impact the results of a calorimetry experiment, leading to inaccurate calculations of energy content in food. Let's examine these errors one by one:
- a. Misreading the scale and recording a higher final mass will lead to the calculation of a smaller temperature change for the water. This is because you'll assume more water absorbed the heat. Consequently, the calculated kilocalories per gram will be lower than the actual value.
- b. If part of the marshmallow fell off before the final mass was determined, it would mean that the mass used in the calculation was too large, resulting in a calculated value that is higher than the true calories per gram.
- c. Having to relight the food multiple times could cause a loss of some energy to the surroundings each time, decreasing the total heat transfer to the water. Thus, the final value for kilocalories per gram would be lower.
- d. Measuring the temperature in the air above the water and not in the water itself would give a lower final temperature, as air heats and cools more rapidly than water. This would falsely increase the temperature change calculation, leading to a higher calculated kilocalories per gram.
These errors will either underestimate or overestimate the heat change, leading to incorrect kilocalories per gram results when compared to an error-free calorimetry process.