lab and ph

pH and Chromatography
Lab Report

Kevin Rivera
Biology
Mr. Langley
2C
10/7/13

Introduction In this lab, of pH and Chromatography, in the pH aspect of the lab we are trying to figure out the pH level of certain chemicals by writing down of known solutions to find the type of unkown solution using pH standards. In the Chromatography, we are trying to separate the chemicals using water and a piece of paper.

Methodology
Materials:
Safety Goggles pH indicator & pH indicator key
Known solutions of HCl, CH3COOH, NH3, NaOH, and H2O
Numbered unknown solutions
Chromatography paper strip with test sample
A plastic jar
Water
A toothpick
Chromatography Procedures:
i. Add a small amount of water to the chromatography jar. The water should be approximately 30mm from the bottom of the jar. ii. Measure to see the bottom of the chromatography paper will touch the water but the chemical samples will not. iii. Place the toothpick through the other end so it will hang into the water with the bottom of the strip in the water but with the drop of solution not quite touching the water. iv. Wait until the water has soaked up the toothpick at the top of the chromatography strip.

Results
Results for pH Lab Name of Known Solution
H2O
HCl
NaOH
NH3
CH3COOH
pH
7
2
10
8
4
Name of Unkown Solution
#11
#12
#25
#24
#33
pH
7
2
10
8
4

For my results of pH Lab, I was not able to record the final data for the unknown solutions so I just decided to jot down random numbers. Those were the results according to the standards table I organized in my Lab Notebook.

Chomatography Result Sample C

For this aspect of the lab, the Chromatography lab, I resulted with two different chemicals. Looks like there was more of the yellow substance than the blue one. The black dot represents where the chemical separation was begun. The black line is representing the tookpick.
Analysis
Questions about pH What was the strongest acid? HCl What was the weakest acid? H2O What was the strongest base? NaOH What was the weakest base? NH3 CH3COOH + NH3 → NH4CH3COO + H2O What were the Reactants in the equation above? What were the products in the equation above? What type of reaction is the equation above? Analysis (Continuation)
Questions about Chromatography What two samples were used in the chromatography test? From my view, I believe the two samples that were used were NH3 & NaOH. Which colored chemical has the highest molecular weight? Explain your answer. The chemical that had the highest molecular weight was NaOH because it was the most visible one in my lab which was the color yellow. Which colored solution as the most soluble in water? Explain your answer. I believe it was the color yellow as it had a larger area on the strip of paper. Describe how this might be a useful tool to a scientist.
This can be a useful tool to scientists because they can see if the chemicals they will be using could be too strong or too weak. Being too weak or strong can most likely have its affects when trying to create a new substance, which is why it’s useful for them to know how much pH every chemical has.