This error yielded a much larger error than 0.22s so we must use +/- 8.22 as our absolute error.
* Tablet was chipped
* When the tablet was dropped water splashed out
* Hard to know when reaction finished
* The mass of Alka-Seltzer might have been different
The attached graph shows the proportionality of the amount of water to the amount of time it took to complete the reaction
In order to figure out the proportionality we must calculate the slope.
Calculation of proportionality constant:
Therefore the equation that represents the proportionality between the amount of water and the reaction time would be:
Where T is time and W is amount of water.
In order to find error with our proportionality we must add error bars into our graph. [Note: Our error bar in the x direction was set to 3 because the error in the graduated cylinder was 1%, so we took the largest value and used that as our error. The error in the y direction was from using the range method above]
To find the error in the proportionality constant we must use k-high and k-low, being the steepest and shallowest slope. Using these we subtract them and divide by 2.
Therefore the new equation for the proportionality is
Our relative error is now
Conclusion and Evaluation
We determined that the proportionality between the time it took and the amount of water