Graphing the 1st Derivative on excel?

[higherme]

I have a titration curve (pH vs NaOH added) and i want to determine the endpoint of this graph
i want to use excel to make a graph of it's derivative (dy/dx) but i don't know how?

does anyone know how?
is there an option i can choose when making the graph?

 

[chemisttree]

You can calculate dy/dx (actually delta pH/delta volume) and graph the result. Pretty straightforward that way.

 

[Blueshift5]

I would suggest using the built-in graphing tools in Excel to plot the first derivative of your titration curve. To do this, you can follow these steps:

1. Plot your titration curve as a scatter plot in Excel, with pH on the y-axis and NaOH added on the x-axis.

2. In a separate column, calculate the first derivative of your data points using the formula = (y2-y1)/(x2-x1), where y2 and y1 are the pH values at two adjacent data points and x2 and x1 are the corresponding NaOH added values.

3. Plot the first derivative data points as a scatter plot, with the same x-axis as your titration curve.

4. To make the graph easier to interpret, you can add a trendline to your first derivative data points by right-clicking on one of the data points and selecting "Add Trendline." Choose the "Linear" option and check the box for "Display Equation on chart." The equation of the trendline will represent the slope of your first derivative at each point.

5. The endpoint of your titration curve can be determined by identifying the point where the slope of your first derivative graph becomes close to zero. This indicates a flattening of the curve and therefore the endpoint of the titration.

I hope this helps and if you need any further assistance, please don't hesitate to ask. Excel is a powerful tool for graphing and analyzing data, and I'm sure you will be able to successfully plot the first derivative of your titration curve using these steps.