Carbon dioxide from an antacid tablet

[Hyperfluxe]

Homework Statement

Let’s say the % concentrations of CaCO3 (table 5) you obtain from trial #1 and #2 are consistent, while the concentration obtained from trial #3 is significantly higher. Demonstrate, how and where, a wet flask could be involved to explain such a result. Explain in great details.

Homework Equations

The equations under Calculations
https://docs.google.com/open?id=0By9VwoUlJRdCMzgxYjM1YzQtODA3MS00YmM5LWJiNjYtYmRlNDUwNDNjYTI3

The Attempt at a Solution

Alright, so we did a lab with calcium carbonate and antacid today, reacting each with HCl and measuring the pressure/temperature before the reaction and then after the reaction. From this we can find the volume, amount, mass, etc. I have no idea as to how to approach this question, it seems as it wouldn't depend on whether the flask is wet or not - because a wet flask with release more CO2 but how does that contribute to the final concentration of calcium carbonate in an antacid tablet? Any hints would be appreciated.

 

[Borek]

Wet flask will not release MORE CO₂. CO₂ will start evolving before you start to collect it, so you will not collect everything.

Imagine you collected all of the gas and it was 44g of CO₂ - how much CaCO₃ was present?

Now imagine gas started to evolve too early and instead of 44g you collected only 1g. Use the same stoichiometry to calculate how much CaCO₃ was present. Is it a positive, or negative error?

 

[Hyperfluxe]

There would be a LOWER concentration of CaCO₃ then! So the answer to the question would be NO, because if anything it would be a lower a concentration? Of course I have to back that up with reasoning + stoich. To answer your question, there would be 1g of CaCO3. What do you mean by postive/negative error?