ibquestions Posted May 27, 2011 Report Share Posted May 27, 2011 I need to test the pH of some soil samples I have, using the strips (the scientific names for them have completely escaped me right now) didn't do what I wanted them to because I wan't an accurate measurement (for example a pH of 6.7) not just a range (6-7). I was therefore wondering if anyone knew the following: What is an accurate way to test the pH of soil? I have a pH probe handy at my school, but apparently I need to make a solution with it in order to actually test the pH of the soil samples I have? How much soil will I need to actually get these samples? Thank you for any help, it's much appreciated Reply Link to post Share on other sites More sharing options...
Drake Glau Posted May 27, 2011 Report Share Posted May 27, 2011 This is more of a "trial and error thing", I'd suggest just making a rather thick solution with the soil but keep the mass of the soil used and volume of water used constant for every sample once you have decided how much of each to use. Reply Link to post Share on other sites More sharing options...
ibquestions Posted May 27, 2011 Author Report Share Posted May 27, 2011 ah sounds good, thank you very much Reply Link to post Share on other sites More sharing options...
ibquestions Posted May 31, 2011 Author Report Share Posted May 31, 2011 one more question for anyone who can answer should the pH of soil close to an ocean be more acidic or basic? Reply Link to post Share on other sites More sharing options...
Drake Glau Posted May 31, 2011 Report Share Posted May 31, 2011 Hmm NaCl is a strong acid and strong base =/ I'd go with basic though. Acidic things are generally sour and I've tasted sea water before Reply Link to post Share on other sites More sharing options...
ibquestions Posted June 2, 2011 Author Report Share Posted June 2, 2011 Thank you I am going to be a pain and ask one final question (sorry ) okay, so i have conducted my experiment by collecting soil samples and using a quadrat technique, etc... but now I can't seem to figure out what the independant, dependant and controlled variables are... i know the pH is the dependant variable... but i am not changing anything to create this. I used random sampling and a quadrat technique to get soil samples and count the number of ferns in each quadrat (to see how pH affects the distribution of this fern species) but where exactly do factors such as "sunlight, moisture, etc" fall? Are they independant varibales? controlled variables? I am so confused Reply Link to post Share on other sites More sharing options...
Drake Glau Posted June 2, 2011 Report Share Posted June 2, 2011 Ewww there is no IV really. You tested a correlation of pH vs fern#. pH is your "IV" or your x variable and the fern count is your y variable or your "DV" in this case. This is rather weird. I did something similar for bio but I was able to control a ton of variables =/ Basically you need to do some math with your data (standard deviations, chi squared testing, something) to see if the two variables have any sort of relationship.Those factors are going to be factors you didn't think of when measuring and need to brought up in your evaluation. Reply Link to post Share on other sites More sharing options...
ibquestions Posted June 2, 2011 Author Report Share Posted June 2, 2011 (edited) hmmm this is a difficult lab hahah might i ask what exactly standard deviations/chi squared testing is? EDIT: oh... and how did you manage to control the variables? :/ Edited June 2, 2011 by ibquestions Reply Link to post Share on other sites More sharing options...
Drake Glau Posted June 2, 2011 Report Share Posted June 2, 2011 Controlling variables for heart rate is a lot simpler Ummm, crud...you're not going to be able to learn both of those or even one by the time this lab is due =/ Just plot a graph of pH vs fern#, make a line of best fit, and point out some trends in the data and that will pass for processing. Then in your conclusion followup on those trends you pointed out and tie it to what they actually mean. Reply Link to post Share on other sites More sharing options...
ibquestions Posted June 2, 2011 Author Report Share Posted June 2, 2011 hmmm damn, okay thank you! Reply Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.