In a laboratory, a student studies the absorption and transmission of light in order to analyze copper in brass and determine its percentage within the brass sample.
He determines the amount of light absorbed by a sample by measuring the amount of light transmitted, all at a particular wavelength. A standard solution of pure copper is used as well as a solution from the brass. The copper solution will be diluted several times to have varying concentrations. The absorbances of each of these known solutions at the particular wavelength are used to create a Beer's Law plot. The concentration of Cu^2+ ions in the brass sample can be calculated.
Now here are the questions:
Explain whether the following factors would increase, decrease, or not affect the percent copper in the brass sample in the experiment described above. Include a brief explanation.
1) The mass of the copper wire was recorded incorrectly larger than its actual value.
2) The mass of the brass was recorded incorrectly lower than its actual value.
3) The copper wire solution was diluted to 100 mL instead of 50 mL.
4) The copper wire and brass solutions were both diluted to 100 mL instead of 50 mL.
5) A student wet the filter paper with deionized water to hold it in place before filtering the tin (IV) oxide from the brass solution.
6) In the quantitative transfer of the standard copper solution, one drop (0.05 mL) of the solution was lost.
I'm completely lost on this. Obviously, I don't expect the answers just given to me, but I'm not sure how to even approach this. I thank anyone that can help! :)
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