Ph Buffer Using Cabbage Indicator

4. It would be difficult to measure the concentration of acid in red wine or coca-cola because the colour of the drink is too dark for us to see when the phenolphthalein indicator changes colour. You could overcome this difficulty by using a pH meter.

If the broth turns yellow, it means that acid was produced and reported as A. If the organism can break down the amino acids be de-amination and ammonia is produced, this will raise the pH level turning it pink. This alkaline result was reported as K.

Vinegar is a common household product, when mixed with the indicator, phenolphthalein, it turns pink. This indicates that Vinegar is acidic.

Purpose/Hypothesis: The purpose of this experiment is to use both cabbage juice and pH paper to determine the pH of household items. This way, we can tell which products are basic and which one are acidic. If we use cabbage juice as an universal pH indicator by comparing it to pH paper then pH determined by the cabbage juice will be unstable because by using cabbage juice, it can be different depending on how diluted it is.

The null hypothesis will be that the test tubes with an increase in temperature, pH values, enzyme concentrations, and substrate concentration will have a very small color change or no color change at all. The alternate hypothesis is that the test tubes containing an increase in temperature, pH values, enzyme concentrations, and substrate concentration will all have an intense color change; the more the change, the more intense the color change will be.

“The pH of a solution is a measure of the molar concentration of hydrogen ions in the solution and as such is a measure of the acidity or basicity (sic) of the solution. The letters pH stand for power of hydrogen and the numerical value defined as the negative base 10 logarithm of the molar concentration of hydrogen ions.” (PH, 2002). The pH scale is from 0 to 14. When the pH is higher, the hydrogen ions are fewer and the substance considered alkaline. This means when a pH unit increases by one, there is a tenfold change in the hydrogen ion. For example, if a substance has a 7 pH, it has 10 times as many as hydrogen ions available as 8 pH. A lake having a water pH between 6.5 and 8.5 is considered to be neutral. Researchers tested Peckham Park lake water monthly from August 2015 to April 2016 for water pH levels. A water quality PH test strip taken from a jar and dipped into the lake. After a few minutes, the strip will turn a color and this color determines the pH. The jar the strips came in has a chart of the colors on the back which compared to the color on the strip. The lake tested monthly using the PH test strips, which show the pH level, hardness, toxic, etc. using color-change

2. We measured 1 mL of turnip peroxidase (the enzyme) and 3 mL of neutral buffer (pH corresponding to the test tube number i.e. pH 5 in test tube 5) with a syringe and disposed it into tubes 3, 5, 6, 7, 8, and 10

To improve the results from the experiment buffer solutions that were not whole pHs could have been used e.g. pH 4.5, 5.5 etc. This would have provided more reliable results as a wider range of results would have been produced. Using pHs with decimals would also help to more accurately determine the optimum pH as the optimum may have been above or below the pH stated in the hypothesis; 8. In this experiment however the optimum is taken at 8 because the graph does not rise again.

Table 2: Consists of color extract taken from a red cabbage for a natural indicator. The pH reading that was measured by using the pH meter and the result of the pH reading to determine whether the solution was acidic or basic.

Measure and add 5cm3 of buffer solution using a measuring cylinder with the pH 3 into a test tube using a pipette and place the potato cylinders into the test tube.

The purpose of this experiment was to determine the pKa of the bromothymol blue (indicator) through absorption spectroscopy. Bromothymol blue being a monoprotic acid base indicator, displays different colors at different pH because of the differences in the ratio of the conjugated acid and base form. The fraction of conjugate acid and base was interpolated for the solutions through the acquired absorbance spectrum of the bromothymol blue at various pH. The rearranged form of Henderson Hasselbalch equation was graphed as a function of pH to determine the pKa of the indicator.

My science fair topic will be measuring the acidic levels in different companies of water bottles such as Aquafina, Dasani, Evian, Fiji, Miami Dade Tap Water, Penta, Publix Spring Water, Smart Water, Smart Water, Volvic, Voss, and Zephyrhills. Bottled water has been tested for its ppm (parts per million) to measure the amount of particles inside the water. The pH scale is a measurement of how acidic or basic an aqueous solution is. The pH scale has a range of 0-14; numbers less than 7 are considered acidic and numbers greater than 7 are considered basic. An acidic pH level means that the solution has more free hydrogen ions, and a basic pH level means that the solution has more free hydroxyl ions. pH is reported in logarithmic units and an increase or decrease of one on the pH scale has a 10-fold change. The negative logarithmic of the hydrogen ion concentration calculates the pH level of a solution. This is why pH stands for the potential of hydrogen and it calculate din

By using acid-base titration, we determined the suitability of phenolphthalein and methyl red as acid base indicators. We found that the equivalence point of the titration of hydrochloric acid with sodium hydroxide was not within the ph range of phenolphthalein's color range. The titration of acetic acid with sodium hydroxide resulted in an equivalence point out of the range of methyl red. And the titration of ammonia with hydrochloric acid had an equivalence point that was also out of the range of phenolphthalein.. The methyl red indicator and the phenolphthalein indicator were unsuitable because their pH ranges for their color changes did not cover the equivalence points of the trials in which they were used. However, the

First, three titration curves and three second derivative curves were created to determine the average pH at the half-equivalence point from the acetic acid titrations. Titration curves were used as visuals to portray buffer capacity. The graphs and a table, Table 1, that showcased the values collected were created and included below. The flat region, the middle part, of Figures 1, 2 and 3, showed the zone at which the addition of a base or acid did not cause changes in pH. Once surpassed, the pH increased rapidly when a small amount of base, NaOH, was added to the buffer solution. Using the figures below and

In this lab a acid-base indicator phenolphthalein was used to determine endpoint of a reaction HCl(aq) and KOH(aq). At the end point all of the HCl(aq) would have reacted with KOH(aq), and the pH becomes 7. The phenolphthalein would changed colours from colourless to pink indication when enough KOH(aq) was added. The purpose of numerous trials was to use the average volume of the 3 trials with similar measurements.