Acid Base Indicator Lab Report

The Benedict’s test is useful for reducing sugars. Reducing sugars are a carbohydrate that can either be straight chains with an aldehyde group at the end or as ring forms with a ketone group (Hill, 1982). Monosaccharides and most disaccharides will reduce copper (II) sulfate. The Benedict’s solution contains cupric ions and the aldehyde groups at the end of the sugars will reduce the cupric ions to cuprous ions (Cu+). There will be a precipitate of copper (I) oxide when the cuprous ions combine with oxygen (Hill,

The Blood agar is a bright red, opaque plate and the streaking or the inoculation technique was a modified streaking for isolation with a heavy quadrant one. This is where the antibacterial disc bacitracin was used to determine the bacteria’s susceptibility.

The Bile Esculin agar test has its medium as selective and differential. Black medium shows a positive result for esculin hydrolysis. In the agar, Gram-positive cannot grow in the presence of bile while certain Gram-negative bacteria can hydrolyze esculin with bile present. MR-VP broth contains glucose and peptone. The enteric bacteria will oxidize glucose for ATP, but there are different fermentative pathways that allow glucose to be fermented.

It takes non-acidic potassium iron out of the stomach and replaces it with an acidic hydrogen ion, which makes things acidic. By putting more hydrogen ions into the stomach, the pump makes its contents more acidic. But acid secretion into the stomach stops when a person takes a proton pump inhibitor that stops the proton pump from working. PPIs stop cells in the lining of the stomach producing too much acid. This can help to prevent ulcers from forming or assist in their healing process.

The effects are red bright skin. In lab, we learned to distinguish two types of bacteria using the gram stain, gram positive and gram negative. Since S. Aureus has a thick peptidoglycan cell wall with teichoic acid, it stains gram positive. Further tests will indicate the bacteria, including the presence of catalase, sheep blood hemolysis, mannitol fermentation, halotolerance, and coagulase, which S. Aureus is positive for all. 3.)

Water will act as initial solvent for caffeine extraction. This is due to water that slowly soluble with caffeine at ambient temperature but highly soluble when temperature is at 100°C. Then, methylene chloride is chosen as the extraction solvent, due to its miscibility with caffeine and immiscibility with water. As mentioned above, the immiscible pair is chose for the extraction part because to allow the aqueous and organic layers to be separated. Basically, the bottom layer is the aqueous layer while the upper layer is the organic compound.

Based on the references take, a mixture of extra virgin and light olive oils would most likely have features resembling regular olive oil. It would have a lighter but still bright yellow color, and a wavelength and absorbancy between the ranges for extra virgin and light olive oil. Without the use of a spectrometer, the concentration of an unknown solution of nickel (II) nitrate could be estimated based on the coloring. The more concentrated the solution the darker green in appears and, vise versa, the less concentrated the lighter the solution will become as it is diluted by water. You could use Beer’s Law to calculate the unknown concentration of cobalt (II) nitrate as Beer’s Law states that a solutions concentration is proportional to the solutions concentration.

Explain the relationship between the ionisation of amino acids and pH |Structural diagram of the neutral structure| |Structural diagram of positively charged structure| |Structural diagram of negatively charged structure| Explain how the form of an amino acid, whether positively charged, negatively charged or neutral, depends of the pH of the solution ? If you increase the pH of a solution of an amino acid by adding hydroxide ions, if this is done then the hydrogen ions will then be removed from the -NH3+group . . To test if it is now a negative ion a process called electrophoresis.although it is colourless its position can be detected using ninhydrin. If the amino acid has dried and then heated gently it would appear as

Primarily, acid stimuli produce a sour responese at a very low concentration, which is transduced by the chorda typani. When the concentration of sour taste response is high, it cause the irritation and is transducted by the trigeminal nerve.The lenghtening of alkyl chain structure of acid favor the diffusion through the membrane, this property shows that the chemical nature of sour taste receptors are like lipids instead of

Ali Atwi : Internal assesment – calculating of the concentration of ethanoic acid in vinegar AIM : To calculate the concentration of ethanoic acid CH3COOH in vinegar using stoichiometric equations, ( Yamaha brand ) Introduction : I personally like to add a little bit of vinegar on my food because it makes it taste better, yet I know that vinegar contains acid, and I also know the consequences of highly concentrated acid intake, like severe itching and stomach ache, vomiting. Venigar contains a small percentage of ethanoic acid Ch3COOH. This practical aims to find out the concentration of the of the vinegar against a standard solution of sodium hydroxide soloution of concentration 0.1 mol dm3 through acid-base titration, the label on the bottle says 6%. The equation of the reaction between sodium hydroxide and ethanoic acid is as follows: CH3COOH + NaOH → CH3COONa + H2O We can measure the end point of titration process and we can also measure the amount of reactants. The concentration of ethanoic acid in the vinegar can be determined through stoichiometric calculations, Using the values obtained from the titration, and also the chemical equation as a reference.