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Experiment Title

Indication of pH and Buffer Solutions Statement of Purpose Train the preparation of the acetate buffer solution (pH = 4.8) and other solutions. Practice the pH measurements. Test the buffer capacity of the prepared buffer solution.

Hypothesis to test:

- property of buffer solution to keep pH, when the strong acid or base are added; - red cabbage juice acts as a natural indicator, which helps to identify the pH of the solution.

Description of the Experiment

Acetate Buffer Preparation: mix 10 ml of 0.2 M acetic acid with 15 ml of 0.2 M sodium acetate, add 75 ml of distilled water was added. Store in an ...

Overview: Overview: Antigen-antibody reactions are commonly used in immunological assays. In a traditional agglutination assay, the end product is a visible antibody-antigen complex that settles as visible particulate matter in the solution. In other cases, the reaction is invisible and wants the use of a specific enzyme or isotopic probes that can amplify the signal created by the antigen-antibody reaction, so that they can be detected with the naked eye or an ELISA/RIA reader1. Hemagglutination is a visible antigen -antibody assay in which soluble antibodies react with antigen on the surface of (red blood cell) RBC to form a ...

Introduction

This experimental study has been carried out to determine the corrosion behavior of Type 316 stainless steel when it is exposed to chloride solution, which is usually a substantial component of sea water. The inherent corrosion behavior of stainless steel takes place in two phases as demonstrated in the morphological evidence the test pieces. The initial phase entails induction process, and it is followed by a breakdown of passivity, which culminates in the active dissolution of the material. The corrosion experiment is based on an electrochemical technique whereby the seawater acts as an electrolyte medium, whereas the test pieces ...

Introduction

The kinetic characteristics are important for the design of chemical engineering processes. They allow assessing the time required for the reaction and choosing the temperature range suitable for the reaction. The reaction path is observed by measurments the transmittance of the Crystal Violet solution that reacts with sodium hydroxide. The concentration, and the color of the solution changes with the reaction flow, and this is measured by the spectrophotometer.

The data are plotted as concentration - time and logarithm concentration time, and the reaction rate is:

Rate = [Crystal Violet] [Sodium Hydroxide]. Using the excess concentration of one of the reagents, the reaction rate with respect to the other reagent is found from logarithmic plot (Rahul & Chakrabarti ...

The objective of this experiment was to prepare Beer-Lambert calibration curves for different forms of nitrogen and to determine the concentration of nitrate, nitrite, and ammonia ions in different water samples from the Biscayne Bay.

Introduction

Nitrogen is the most abundant element in the Earth atmosphere. In is not surprising that it is one of the most crucial elements not only to human life but all life on our planet. The chemistry of nitrogen is rather diverse because it can exist in different oxidation levels – from +3 to -5. Due to its large impact on the biosphere, the circulation of ...

Discussion

Temperature, pH and enzymes are some of the factors that are known to influence the rates of biological reactions (Almeselmani &Moaed et al. 382-3). The action of enzymes (being biological) is controlled by temperature and pH. It was hypothesized that in test tubes 2 and 4, under the influence of temperature, the reactions would be much faster because the molecules moved faster at higher temperatures. However, as attested by the results, with respect to observable color change, test tube 2 did not react to the higher temperature. Test tube 2 remained clear at different temperatures. This was attributed to ...

An organic molecule refers the molecules of living things composed of carbon atoms organized in rings or chains on which other elements like gasses (nitrogen, hydrogen, and oxygen) attaches themselves.

Purposes of the experiments

The experiment would test food sample for the presence of organic molecules i.e. proteins, polysaccharides, and sugar.

Question

Would reagent used in this experiment identify the organic molecules? Hypothesis Reagents Benedict’s solutions, Biurets solution, and iodine would establish the presence of sugars, proteins, and starch respectively. Setup of the experiment Materials Benedict solution that is a blue in color and contains copper ions. It is used in the laboratory ...

1) Iodine test.

Iodine test distinguishes starch. It helps in distinguishing a polysaccharide from monosaccharide, disaccharides and other polysaccharides. The test is also called iodine staining. The iodine reacts with coiled polymer molecules and turn bluish black. Non-coiled starch does not react with iodine thereby no bluish color observed. A positive result is when there is the presence of the bluish black color.

Procedure

1. Put two drops of the solutions to be tested in three different test-tubes. 2. Add two drops of the IKI reagent to each of the tubes containing different sugar solutions. 3. Keep the sugar at room temperature ...