Text submission by student for pre-lab CPR

Dear Ms. Leadbetter,

In this experiment we tested presence of lead in paint samples from different origins to acquire the percent weights of each. In this experiment we used an Atomic Absorption Spectrophotometer (AAS) to collect data and find the presence of lead. The purpose/goals of this experiment were to determine whether lead was present in the samples and to decide the degree of health concerns associated with each sample from it's percent weight. Lead is absorbed through the stomach to the bloodstream, esp. children, and health concerns include slow mental development, impaired hearing, and toxic effects in the kidney and red blood cells.

In this experiment we used a Mohr pipette to dilute the powdered paint chip sample. To use the pipette one would put the tip of the pipette in to the solution and turn the dial with their thumb to the proper volume. To release the substance you simply turn the dial the opposite way. A solution of lead was provided and using the pipette we were able to mix the proper solution.

The AAS detects lead in the unknown paint samples by measuring the amount of light absorbed while in a flame. In this process the sample is converted into an aerosol form and shot as a light beam from the Hollow cathode lamp (HCL) through a flame which oxidizes or reduces the sample. This will produce elemental forms of the atom being tested by going through a monochromator which isolates the analytical lines. It then goes to the photomultiplier tube which determines the intensity of the photons.

In this experiment we were able to detect, using the AAS, whether their was lead present in the samples, and if so the percent weight of the lead. From these results we were able to determine the health concerns represented.

Sincerely,

Average peer rating 5.0/10

Self-assessment 5/10