I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was..

36.4% NaCl
36.4% SiO2
40.9% CaCO3
the total % recovered was 113.7% with a 13.7% error. I do not understand how we recovered more that the original sample. One of the post lab questions ask
1. List possible manipulation errors that might contribute to the following errors:
-obtaining a significant larger amount of NaCl than as present in the original sample;
-Obtaining a significant small amount SiO2 than was present in the original sample.

help me please! I thought maybe the physical form of the NaCl changed the mass after the boiling off process, I have also thought about the chemical bonding process, but it doesn't make an sense to me.

and 4.

It seems like you're trying to understand why you recovered more than the original sample in your lab experiment. There could be several reasons that contributed to this discrepancy. Let's address each possible manipulation error separately:

1. Obtaining a significantly larger amount of NaCl than was present in the original sample:
- One possible manipulation error could be incomplete separation of NaCl from other compounds. For example, if the separation method used was not effective enough to completely separate NaCl from SiO2 or CaCO3, you might have ended up with more NaCl in the recovered sample.
- Another factor to consider is the possibility of contamination. If there was any additional NaCl introduced unintentionally during the process, it would contribute to an increased recovery of NaCl.

2. Obtaining a significantly smaller amount of SiO2 than was present in the original sample:
- The incomplete separation of SiO2 from other compounds could also be a contributing factor here. If the separation method used was not efficient, you might have lost some SiO2 during the process, leading to a lower recovery.
- It is also essential to assess the accuracy of the measurement techniques employed. If the weight or volume of the SiO2 was not measured accurately during the experiment, it could lead to an underestimation of the recovered amount.

Regarding your thoughts on the physical form of NaCl changing the mass after the boiling off process, it is unlikely to be a significant factor. Changes in physical form, such as changes in solubility or evaporation, usually do not alter the overall mass of a compound.

Chemical bonding processes would not directly affect the recovery of individual compounds unless there was an unintended chemical reaction occurring during the separation process. However, based on the information you provided, it does not seem to be a plausible explanation.

It is worth mentioning that experimental errors are common, and a 13.7% error is not unusual in laboratory experiments. Nonetheless, a critical analysis of potential manipulation errors can help identify areas that require improvement in future experiments.