Firstly, thank you to anybody who is willing to help. No math teacher can help me here so i'm relying on your help.

1. I conducted a series experiments to measure CO2 given off of yeast in a 30 minute window at different temperatures, of course there was a 'normal' correlation displayed (less activity as we stray further from optimum enzyme temperature):

Null Hypothesis:- There will be no difference in the rate of respiration as the temperature is manipulated.

Experimental Hypothesis:- There will be a difference in the rate of respiration as the temperature is manipulated.

2. I then plotted each individual experiment (refer to image) as a scatter plot, this displayed curvilinear? data as the CO2 production slowed down towards the end of the experiment

3. I calculated the gradient of the graph (Delta Y/Delta X), giving me the rate of reaction for each experiment.

4. I need to conduct statistical analysis into this data. I tried using chi-squared however the p value stated the results were down to chance; obviously rubbish

Am I using the test improperly or should I be using a different test? I think it is interval data, please suggest a test I could possibly use, bearing in mind the rate values follow a normal correlation in relation to temperature (peaking at 50 degrees)

I have included pictures of the scatter plot, also of the rate values in relation to temperature and of course the attempt of a chi-squared test.