# Homework Help: Potentiometric titration by ''mathematica''

1. Nov 14, 2012

### emissivity

1. The problem statement, all variables and given/known data

as you know, potentiometric titration's data makes this graph.

and first derivative, 2nd derivative etc..

I haven't tried this experiment yet.
So I'd like to try this by the data which I just make by myself.
this is not my real data.

data = {{0, 1.0}, {2.5, 1.2}, {5.0, 1.3}, {7.5, 1.5}, {10.0,
1.7}, {12.5, 2.0}, {15.0, 7.0}, {17.5, 11.9}, {20.0, 12.1}, {22.5,
12.3}, {25.0, 12.4}, {27.5, 12.5}, {30.0, 12.5}}

2. Relevant equations
derivatives

3. The attempt at a solution

1. I plotted the data.
ListPlot[data]

2. and I used interpolation.
f=Interpolation[data]

3. I plotted the graph
Plot[f[x], {x, 0, 30}]

there is a problem. If you try this, you would find out, near the end point, it doesnt fit well.
I want the graph just like the link as I mentioned first

well.. I know that I can draw these graph by my hand by the excel.
just write the data,
plot the graph,
and I find dy/dx one by one
and draw the 1st derivative graph,
and d2y/dx2 one by one..
...

but

as you know,
I think this stupid doing is not good

So I just want to plot the data easily by the mathematica..

is there any way to draw the data easily?
or just I have to plot the graph one by one?

2. Nov 14, 2012

### Staff: Mentor

Try to use more data points, and make them more dense around the important places.

Not trhat I know it will work, just guessing.

3. Nov 14, 2012

### emissivity

dear borek

then could you help me plot the 1st derivative graph?

4. Nov 14, 2012

### emissivity

well I got it

but I don't know how to delete this post

I'll figure it out

wait a sec..

5. Nov 14, 2012

### emissivity

well....

is there anyone who can tell me how to delete this post?

sorry..

6. Nov 14, 2012

### Staff: Mentor

Edit -> delete

But the edit courtesy time is limited.