Chicago River Lab

3 Things I Learned in this Lab:

1. Chicago has 37 moveable bridges. 
2. The Michigan Avenue bridge is a double-lear, double deck bascule trunnion bridge. 
3. Chicago bridges are painted red to recreate the original paint color, which was red lead paint (to prevent rusting) mixed with black powder (to tone down the red). 

2 Things I Found Surprising in this Lab: 

1. I was surprised that the Chicago River was so clean according to all of our tests; I've grown up in Chicago and have been told by my whole family to never swim in the river or even go too close to it for fear of pollution. However, the tests we performed in this lab disproved their theories of its severe pollution. 
2. I was surprised that the bridge requires so little energy to be moved. In the museum, a sign said that the amount of energy needed to lift the bridge is the amount of energy in a 1950s Volkswagen Bug motor. 

1 Question I Have After This Lab:

1. Who/what else was affected by the River's pollution before the flow was reversed? Because of the amount of pollution and untreated sewage that went into Lake Michigan, which is so large and connects so many places, what other places or people were affected?

The test I did was of the Chicago River's pH. This test measures the concentration of hydrogen atoms and the acidity of a fluid. This is important because too much or too little acid in a river can be dangerous for the environment in and around the river. We took a sample of river water, placed a pH testing fluid in, waited for the water to change color, and then matched that color to one on a chart to see what the pH was. 

Based off of the Q values found in class, we can classify the river's quality as excellent. However, we were so close to the lake that our results might have been tainted by the low percentage of actual river water. However, this could be improved if fewer things are put into the river; for example, runoff from chemicals often gets into the river and pollutes it. I personally can work to reduce the number of chemicals I use in my life (in hair products, soap, food, etc.) to cut down on the number of chemicals that could potentially enter the environment. 

Lab 14: Titration

Titration setup

Analyte at equivalence point

For our procedure, we used NaOH, vinegar, and phenolphthalein to identify the percent ionization of vinegar. We first obtained a burette and primed it with NaOH to clean and prepare it. Next, we filled the burette to 50 milliliters of NaOH. We then filled an Erlenmeyer flask with 7.0 milliliters of vinegar, 20 milliliters of water, and 4 drops of phenolphthalein. We then measured drops of NaOH into the Erlenmeyer flask until the solution turned barely pink, which was the point of equivalence of the vinegar. We did this twice and measured that it took 22.30 milliliters to turn the substance pink the first time and  22.10 milliliters the second time.

The percent ionization of the vinegar is .489%. This is so low because vinegar only has 1 ionizable proton (Hydrogen), which makes the possibility of it ionizing very, very small.

Lab 17: Calories in Food

In this lab, we measured the Calories in certain food by burning the food and then measuring how much heat the food let off by boiling water. The amount of heat that the water gained was the amount of water that the food lost, which allowed us to then calculate how many calories the food had.

 

Lab 16: Specific Heat of a Metal

Our setup

Lab 16: Specific Heat of a Metal

For this lab, we were provided with an unidentified metal. To identify this metal, we heated it in a beaker of water and used the changes in the water temperature to identify the heat that the water gained and use the opposite as the energy that the metal lost to find the metal's specific heat. Once we calculated how much energy the metal lost, we found its mass and its temperature change. The specific heat we calculated was 0.17 g/jC, which would make our metal iron.