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# How to plot a straight line graph

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1. I have the following data

I have to plot ln k versus 1/T

The temperature has to be in kelvin, so whatever the temp is in that table add 273.15

Apparently plotting lnk versus 1/T gives a line with R^2 = 1 therefore all these points lie on a straight line.

My question is how would you go about plotting this graph. What I mean is what type of accuracy would you use to plot the x and and y values? Do you have to use same accuracy for both x and y? Does it matter what accuracy you use would you still get a straight line with R^2 value of 1?

Have to plot this on standard graph paper.

Thanks
2. Convert to ln k and 1/T and plot the points on your graphing calculator to get a feel of the graph. Idk what you mean by accuracy, I didn't think of that when I plotted it and it went well. (We did it in Chemistry, arrhenius equation)
3. (Original post by ib_hopeful)
Convert to ln k and 1/T and plot the points on your graphing calculator to get a feel of the graph. Idk what you mean by accuracy, I didn't think of that when I plotted it and it went well. (We did it in Chemistry, arrhenius equation)
I don't have a graphic calculator.

I mean if you work out the values of x and y they are in long decimals in both cases. I'm asking what accuracy should you use because u can't plot exact values.
4. (Original post by khanpatel321)

I mean if you work out the values of x and y they are in long decimals in both cases. I'm asking what accuracy should you use because u can't plot exact values.
2 or significant figures, because the the level of accuracy given in the question is 3 s.f.
5. (Original post by Zacken)
2 or significant figures, because the the level of accuracy given in the question is 3 s.f.
This is from the mark scheme.

If R^2 = 1 , does this mean the gradient calculated from any two points on the line will be the same?
6. (Original post by khanpatel321)
This is from the mark scheme.

If R^2 = 1 , does this mean the gradient calculated from any two points on the line will be the same?
Usually, you try and taking the "biggest triangle" to find the gradient. i.e: don't pick two points close to each other. Pick them far apart.

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