Data from Lab 1 - Soil and Water pH at North-Grand HS, Chicago

Lab 1A – Observing Soil pH

 Data Table #1: Water Sample- PH Measurement

Sample	Color of the pH paper	Approximate pH of water	Acidic, Basic or Neutral
Water	Green/Yellow	7.5	Neutral- slightly basic

Data Table  #2: Soil Sample Observations

Soil sample #	Location	Color	Moisture level	Density – heavy or light?	General granularity – fine grain? big grain?
1	Burlington	Light black	Sticky – high moisture	Heavy	Big grain
2	Prairie	Dark brown	Playdough like moisture	Heavy	Big grain
3	Nancy’s House	Black	Hard and dry	Heavy	Fine grain
4	Raised Bed	Light black	Moist like clay	Heavy	Fine grain
5	Edgardo’s House	Black	Moist like clay	Light	Fine grain
6	Lincoln Park	Gray	Soft and dry	Light	Fine grain
7	Control Sample	Brown	Dry and soft	Light	Fine grain

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Data Table #3: Soil Sample-PH Measurement

Soil sample #	Location	Color of the pH paper	pH of soil	Acidic, Basic or Neutral	Strong or Weak
1	Burlington	Green	8.0	Basic	Weak
2	Prairie	Green/Yellow	7.5	Basic	Weak
3	Nancy’s House	Green/Yellow	7.5	Basic	Weak
4	Raised Bed	Green/Yellow	7.5	Basic	Weak
5	Edgardo’s House	Green/Light Green	7.25	Basic/Neutral	Weak
6	Lincoln Park	Green/Yellow	7.5	Basic	Weak
7	Control Sample	Orange/Light Green	5.75	Acidic	Medium

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Lab Questions Relating to Soil Observations and Soil pH

Questions   Lab Procedure 1-A: Testing Soil pH

1.     Why is it important to know the soil pH?  We need to know the soil pH because we need to know how soils can be different by having acidic or basic pH. It’s important because some plants need basic soil and some plants need acidic soil. If you grow a plant in the wrong soil it may not grow.

2.     What is the range of the measured pH values? The range was from pH 5.75 to 8.0 for a total range of 2.25.  The most different soil was the commercial soil though, which had a pH of 5.75. If we just look at the soil from our neighborhood the range is from 7.25 to 8.0, so it’s only a 0.75 difference which does not seem like very much. We think most of our soils are pretty much the same in our area.   

3.     Is it possible to estimate the pH of soil solely by the physical characteristics of the soil?             It’s not really possible to tell the pH by looking at or smelling the soil. The one soil with very different pH (the commercial soil) did look very different.

4.     What theories do you have for the variation in pH for the different soil samples that were collected for this experiment?  It is recommended that you do some online research to help answer this question. We think that some soils might be more acidic or basic because someone might have put chemicals on the soil as fertilizer or pollution. The amount of rain could also affect how much acid is in the soil. Sunlight could also have an effect.

5.        For each soil sample, including the commercial sample, can you predict which of the plants and vegetables listed in Table 1 would be well suited for growth? The Burlington soil was most basic and would support Pink Hydrangeas and Mint best. The Commercial soil, being most acidic would support Potatoes, Tomatoes and Blue Hydrangeas. The rest of the soils had a pH of 7.5 which would support Beets, Tomatoes, Mint, and White Hydrangeas.  

6. Did any of the results surprise you? The results did surprise us because we thought the pH values would be much more different between the different soils. 

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Data Table #4: Water pH Measurement

Water sample number A	Location	General characteristics of water: color, smell, sediment etc.	Color of the pH paper	pH of water	Acidic, Basic or Neutral
1	Pond	Clear, no smell, light sediments	Orange, green	6.25	Acidic
2	Tap Water	Clear, no smell, no sediments	Yellow, Green	7.25	Slightly basic
3	Lake Michigan	No smell, sand, light sediments	Yellow, Green	7.25	Slightly basic
4	Puddle from in front of school	Smells dirty, dark brown, filled with dirt	Green, Green	6.25	Acidic
5	Evian bottled water	Clear, Clean, no smell	Green, Green	7.5	Slightly Basic

Project Questions   1-B: Testing Water pH

1.     For the collected water samples, what is the range of the measured pH values?

The water samples measured pH values are between slightly acidic, neutral, and slightly basic.

The range was between 6.25-7.5 for 1.25 pH points.

2.     Is it possible to estimate the pH of water from its physical appearance, smell, etc?

No it is no possible to estimate the pH of the water just based on physical appearance and or smell, the water must be tested to find out its pH level.

3.     What theories do you have for the variation in pH for the five different water samples that were collected for this experiment?  It is recommended that you do some online research to help answer this question.

The theory of the variation of the pH for the different water samples is that they vary do to the fact that some water was from a lake which is not only our lake but also our tap water, its is cleaned and purified before we receive it in our homes, bottles water is purified many times before we receive it to drink. So the pH levels all vary do to that fact. Maybe the bottled water company adds something to the water to make it taste better, and that thing is slightly acidic.

4.     Did any of the results surprise you?

No the results are what we assumed them to be. We really didn’t know what to think before the lab, since we assumed most water was neutral pH.

Reflection questions about the week:

1. What did you learn the first week of this program?

we have learned from the first week of this program that there are different people all around the world studying and performing the same type of lab experiments that we do here in Chicago.

2. What worked?

Just about verything about the program so far as been a success in our point of view.

3. What did not work?

We had a hard time judging the pH values of the soil samples. The soil didn’t settle very well and it was hard to tell what color the pH paper was when there was dirt on it.

4. What other comments do you or new questions do you have?

No questions, or comments at this time. Our teacher rushed us a bit. It was hard to get everything done in only one or two classes per week. Some students didn’t quite understand what was going on, but some of us did, so we helped each other.