The pH was found to be 7, which is in the range of a healthy person’s pH (which is 7.4).Benedict`s solution is made up of alkaline copper sulphate and sodium citrate (blue in colour) (Danson and et al, 1996). When it is put in a hot water bath (boiled) when there are reduced sugars, cupric ion is decreased by sugars changing it into an insoluble red cuprous oxide. The solution will change to yellow, orange, green or red, for rising levels of sugar, and will stay blue if no sugar is detected. If the solutions stay the same (blue), the result is negative. In this experiment, the colour remained blue and thus there were no sugars present in the solution.
In the test for a reducing sugar, if it changes to a red orange color is it known as a precipitate as it comes out of the solution and forms solid particles dispersed around the water. The test of non-reducing sugar is striving as a result of if there is any sucrose presents it is broken down into those monosaccharides, which can be proved for using the common reducing sugar test. A positive result indicates that non-reducing sugars are present on the original sample. Sucrose fermentation it involves inoculating of sucrose broth with inoculating loop. Usually done for the differentiation of Enterobacteriaceae species.
This conversion was required to perform a conjugated addition of the alpha-carbon of acetone to 2-nitrobenzaldehyde, resulting in formation of an aldol, which is subsequently converted to Indoxyl. 5mL of 2M Sodium Hydroxide was diluted by the presence of 35mL of water, effectively reducing its concentration to 0.25M. A low hydroxide ion concentration was required to prevent aldol from condensing, which will result in the hydroxyl group leaving as water. Ethanol was subsequently added to reduce the time required for drying
Hydrolysis Rates of Esters Purpose Esters can be hydrolyzed to the corresponding carboxylic acid and alcohol with a decrease in the pH level as the acidic component is formed. The purpose of this experiment is to compare the hydrolysis rates of esters by monitoring the pH values of their aqueous solutions as a function of time. The esters being compared are ethyl acetate, ethyl benzoate, ethyl formate, and ethyl butanoate while the pH level can be determined by the change in color of the solution with the use of sodium hydroxide (NaOH) for the base and the universal pH indicator. The two factors that affect the rates for the hydrolysis of esters is the steric factor and the electronic factor which will serve as the determining factor of how
In the experiment the lemon juice tested to be the strongest acid with a pH of 2 and the pink colour change, the weakest acid was ENO antacid tablets with a pH of 6.1 accompanied by a violet colour change. . In the experiment the Handy Andy or ammonia tested to be the strongest base with a pH of 11.6 and a green colour change, the weakest base was baking powder with a pH of 8 accompanied by a blue-ish purple colour change. And it was also tested that water was slightly acidic with a pH of 7.2. An acid is considered to be a proton donor, this means it dissociates into hydrogen ions in a solution (Wikipedia), this will correspond to it having a sour taste and sharp odour.
ABSTRACT The experiment aims to find the concentration of acetic acid in the vinegar sample by titrating it to a standardized NaOH solution, a base solution. A standardized 0.100 M NaOH solution was prepared from an available concentration of NaOH specifically a 1.00 M NaOH. The volume of the standardized solution (titrant) used which is 0.100 L was calculated using the M 1 V 1 = M 2 V 2 relationship. It was then gradually added to the vinegar solution until the acid-base reaction was completely neutralized. To regulate the reaction, phenolphthalein, an acid-base indicator, was added beforehand to the vinegar (analyte).
This sodium carbonate is dissolved in water and recrystallised to form washing soda. Correct answer is - c 7) Which among the following is a neutral salt? a) Ammonium chloride b) Sodium Acetate c) Sodium chloride d) Sodium bicarbonate e) Magnesium nitrate Hint: It is used in seasoning vegetable salads. Explanation: Sodium chloride is a neutral salt and is used in preparation of food. Correct answer is - c 8) Which among the following is an ingredient in antacid?
Alyah al Mutairi Mr. Washington Biology class H 14.12.15 Deciding the behavior of amylase under the implement of excess pH levels Problem: To verify if amylase maintains to operate with the influence of hydrochloric acid Prelab: Independent variable: pH levels Dependent variable: The effect of pH enzyme action Control: Positive: Saliva and HCL+ saliva Negative: Water Constant: Iodine solution (indicator) Hypothesis: At least two out of the three procedures will be indicated as starch, due to the fact that amylase is the first enzyme that breaks down carbohydrates Materials: • Paper • Pen/pencil • Saliva • Water • Hydrochloric acid • Pipette • Iodine solution • Construction paper • Timer Procedure: 1. A sheet of paper was
(Approximate pH ranges for color change: 8.0-9.8) Low pH values are preferred for Methyl Orange. (Approximate pH ranges for color change: 3.1-4.4) To sum up, back titration is a effective way for the determination of Calcium Carbonate as experimental results were close to it’s true and accepted value of 20%. References Antoine.frostburg.edu, (2014). Acid-Base Indicators. [online] Available at: http://antoine.frostburg.edu/chem/senese/101/acidbase/indicators.shtml [Accessed 12 Dec.
Hanusaiodine solution, chloroform, aqueous KI solution, Na2S2O3 and starch solution is used. Iodine values are calculated from the difference between the blankaand the test sample. For peroxide value; solvent mixture (composed of glacial acetic acid and chloroform), saturated KI solution, starch solution and Na2S2O3 soluiton is used and peroxideavalues are calculated. A) Iodine Value: Hanus Method In this experiment, iodine value of sun floweraoil was determined with Hanusamethod. Blank solution and oil solution were prepared and stored in the dark.