Chem 115 Unit 3 Lab Essay

a. Change the 24th bead to a different color. What does the sentence say now (re-read the entire sentence)? Does the sentence still make sense?

pH was recorded every time 1.00 mL of NaOH was added to beaker. When the amount of NaOH added to the beaker was about 5.00 mL away from the expected end point, NaOH was added very slowly. Approximately 0.20 mL of NaOH was added until the pH made a jump. The pH was recorded until it reached ~12. This was repeated two more times. The pKa of each trial are determined using the graphs made on excel.

We know that that the end point of the titration is reached when, after drop after careful drop of NaOH, the solution in the flask retains its pale pink color while swirling for about 30

1. Develop hypotheses predicting the effect of pyrite and coal on the acidity of water?

The protein molecules in many foods provide the amino acid building blocks required by our own cells to produce new proteins. To determine whether a sample contains protein, a reagent called Biuret solution is used. Biuret solution contains copper ions. However, the chemical state of the copper ions in Biuret solution causes them to form a chemical complex with the peptide bonds between amino acids (when present), changing the color of the solution. Biuret solution is normally blue, but changes to pink when short peptides are present and to violet when long polypeptides are present.

What observations can you make regarding the gene pool and gene frequency of the surviving individuals?

What do the left and rights sides of the brain do? Which side of the brain does a police sketch artist use when creating a suspect sketch?

If new crust is indeed being produced at the rifts, where does the additional older crust go?

3. Experiment: Use the Gizmo to find the carrying capacity with Ample, Moderate, and Little land. List the carrying capacities below.

6-3: This process is used by cells to manufacture _biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products__

The proof (twice the % alcohol) starts at its maximum and goes down (as the alcohol evaporates). If we start with a high concentration of alcohol, we will get the azeotrope (95% alcohol, 5% water) for a while, then the concentration will decrease.

The luminous yellow flame is smoky because no air is entering the burner and hydrocarbon is converted into carbon dioxide

2. The second source of error in the lab is when opening the lid of the crucible which allowed smoke of magnesium oxide to escape. During the lab, we removed the lid a couple of times to allow oxygen to enter the crucible so the magnesium reacts with the air to form magnesium oxide. However, the smoke could have easily escaped from the crucible because of the strong force of heat from the laboratory burner. This could have affected the lab results by decreasing the final mass when some of the product have escaped.

MgSO4 ● 7H2O was obtained by my laboratory instructor. The support ring was attached to the ring stand. The pipe-stem triangle was put on the ring. A dry porcelain crucible was placed on the triangle. A ceramic-centered wire gauze was put next to the support stand. The crucible was heated for 5 minutes with the Bunsen burner flame. After extinguish the burner flame, the hot crucible was placed on the wire gauze from the triangle by using the tongs to cool for accurately determining the mass of an object. The mass of the cooled down crucible was measured. Hydrate was added to the crucible on the balance until the total mass was about 2.2g compared to the crucible alone. Total mass of crucible and the hydrate was recorded. The crucible with the

There are also some elements that are not a part of any type of family. These elements are mostly other metals that are located right after the transition metals. There are some nonmetals that are included in this group. Some of these nonmetals include silicon, nitrogen, carbon, and phosphorus. All elements in this group are some what reactive. Nitrogen is the most common element. Compounds using nitrogen consist of silver nitrate, potassium nitrate, and nitric oxide. Silver nitrate is used in many different chemistry labs.