Biological Evidence Analysis Essay

Solubility matters since organic compounds tend to not be soluble in aqueous solvents, but ionic salts do easily dissolve in water. And acidity matters since we can adjust the base strength to only react with one component of Excedrin at a time, allowing for the components to be isolated. By adding a 1M solution of a basic salt, like K2HPO4 or KOH, to organic compounds, we could convert the organic components of Excedrin into ionic salt that will dissolve in aqueous solvents. Next, by adding a strong acid, like HCl, the Excedrin component is protonated causing a decrease in solubility leading to the component precipitating out of the solution and crystallizing. Acid-base extraction offers a method to separate the active components of Excedrin based on acidity and what bases they will react with.

After all the vapors of the first liquid are collected, the temperature on the boiling plate can be increased so the liquid with the higher boiling point passes through the column, and is collected in a separate vessel. The fractionating column can be packed with glass beads or other such materials to increase surface area for condensation, although that was not done in this experiment. The unknown solution was separated into three falcon tubes. Tube A contained mostly the lower boiling point liquid, B contains both liquids, and C contained mostly the higher boiling point

In a product like soda you would hope that the solute would dissolve in the solvent properly to create the solution, which would be the finished product of the soda. In this case, the solvent is the other mixture of ingredients and the solute is the sweetener that is being used. When making a product such as soda, you would want a solute that would have a high solubility and easily dissolve into the soda. A drink like soda would require a large amount of sweetener to give it to the taste that customers

(139g Acid / 1 mol H+) + (130.g Acid / 1 mol H+) / 2 = 135g/mol H+. The average equivalent mass for the acid is 135g/mol H+. 3. The answer obtained in Question #2 is the equivalent mass of the acid rather than the molar mass because the acid could be polyprotic, which would mean the equivalent mass is different from the molar mass since it is depending on moles of H+ per molecule, and there could be multiple moles of H+ ions in one mole of a molecule. 4.

In the case of phenol the greatest stabilization occurs when the electrophile is added to the ortho or para positions due to the ability of the alcohol to donate electrons into the ring system. Meta addition does not occur as it does not lead to an as stable arenium ion intermediate. This is seen

This would help to identify the unknown meat’s animal of origin better. Introduction: Deoxyribonucleic acid, DNA, is the genetic material of all living organisms, and it is found in the eukaryotic cells’ nuclei. It could be extraction from an unknown tissue sample, assayed and compared to already known sequences in order to find the organism’s source of origin. Molecular analysis of DNA encompasses a series of

Controlled Variables The variables which are controlled are the size of the beaker, the temperature and the volume of the solutions added, such as the distilled water, HCL, sodium iodide solution and the Iron (III) nitrate 9-hydrate solution. The volume must be controlled because each condition consisted of different concentrations of the reactants, the volume would differ in each one. Constant volume was kept to make sure that all conditions had the same number of moles of reactants. Reactions with smaller volumes may have reacted faster than those with larger volumes because successful collisions would occur more frequently.

Their job is to find out if someone had poisons or drugs in their system by testing the blood of the person and eventually test other organs for the presence of drugs or poisons. They also need to calculate the total amount of drugs or poisons in the person system and understand how this could have affected them. After they need to write down a report that could be used in court with the forensic toxicologist being present as an expert witness. Describe the roles and responsibilities of a DNA lab

I believe the process would be the same in that hot water has a faster flow rate causing the substance to disperse faster. However, depending on how dense each substance is will determine how long it actually takes to disperse. Do you believe you would see the same results if you used a different solvent life rubbing alcohol?

Private companies are marketing DNA phenotyping procedure to police agencies to help in identifying a suspect through a visual image. Forensic DNA phenotyping is a young field of forensic genitics. It is the extraction of human phenotypes from molecular analysis obtained from samples in the crime scenes. Latest advances in human genetics have delivered knowledge about the genes involved in external visible characteristics such as hair morphology, pigmentation or body height.

The drawback is that column chromatography is very time consuming; one way to combat this is to utilize flash chromatography, which involves a nitrogen pressure stream pushing the mobile phase through the column. The differences in polarity allow for the effective separation of the various components. The more polar compounds adhere to the polar silica or alumina stationary phase for a longer time. The less polar components elute first and then the polarity of the solvent is increased in order to elute the more polar compounds. Collecting small fractions is essential in column chromatography because they can be combined together; large fractions can lead to multiple compounds in a specific fraction.

so that means that the longer chain will have a slow reaction. It does not have a color and it does not cause fires to happen. It may burn the skin because it is a corrosive substance which is why you should wear gloves when you are handling it. If you swallow the hydrogen chloride then it can be dangerous because it is a toxic substance The bonding in hydrogen chloride is called covalent bonding because nonmetals and metals have the capability to react

3.1 Project Methodology In order to make sure that this project is on track, proper planning and scheduling is crucial. It is necessary to identify the significant key points which are photocatalytic activity of SWCNTs, properties of carbon nanotubes and titanium oxide, available testing procedures using scanning electron microscopy (SEM) and other spectroscopic methods. In this section, a brief detail provided regarding the methods used, sol-gel, hydrothermal and electrospinning. Also, the available tests that will be used are explained.

The group hypothesized that if worms in a bottle had dirt, compost, oxygen, and a good environment they would survive, reproduce, and improve soil. The groups hypothesis was partially supported by this experiment. For one, most worms did not survive. By the end of the experiment 5 worms remained although the group started out with 27.