A student dried a wet crucible with a Kimwipe. A piece of Kimwipe was left clinging to the inside wall of the crucible, The student did not see the piece of Kimwipe when adding the NaHCO3-KCl mixture to the crucible. The crucible ans its contents were weighed and subjected to three heating-cooling cycles (each time the temperature reached 600 Celsius). Could this experimental error significantly affect the calculated percentage of NaHCO3 in the mixture? Justify answer with an explanation.

Heated to what temperature? How big was the piece of Kimwipe? Is the NaHCO3 going to Na2CO3 or Na2O?

Yes, the presence of a piece of Kimwipe clinging to the inside wall of the crucible could significantly affect the calculated percentage of NaHCO3 in the mixture. Here's an explanation of why:

1. Incorrect weight measurement: When the student weighed the crucible and its contents, the weight measured included the additional mass of the Kimwipe piece. This means that the measured weight would be higher than the actual weight of the NaHCO3-KCl mixture alone.

2. Inconsistency in heating and cooling cycles: As the crucible and its contents undergo heating and cooling cycles, the Kimwipe piece can potentially burn or decompose along with the NaHCO3-KCl mixture. This can lead to the loss of some of the mass of the NaHCO3 due to the combustion or decomposition of the Kimwipe.

3. Contamination of the sample: The presence of the Kimwipe can also contaminate the NaHCO3-KCl mixture. During the heating cycles, the Kimwipe can release gases or residues that can react with or mix with the NaHCO3, resulting in a change in the composition of the mixture. This can lead to inaccurate calculations of the percentage of NaHCO3 if the Kimwipe interferes with the reaction or alters the composition of the final product.

To avoid such errors and ensure accurate calculations, it would be essential to carefully inspect the crucible for any foreign objects or residues before adding the NaHCO3-KCl mixture. In this case, the presence of the Kimwipe was overlooked, leading to potential errors in the calculations.