Colorimetric Determination of Ph

At five minute intervals over the next fifteen minute period, record the color intensity of the solution of each test tube.

corresponding to a colour number on the Roche scale. Another salmon colour reference is the

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.

After the serial dilutions of the red and blue dyes were taken, the molarity and absorbance for both dyes were calculated. Using the MiVi = MfVf equation, the concentrations for each value of the red and blue dye were separately calculated. Calculating absorbances calls for setting the correct wavelengths of light for each dye. In this case, the 470 nm wavelength for red dye and the 635 nm wavelength for blue dye was needed to find the maximum absorbances. The absorbance was found by blanking the colorimeter and entering the concentrations. After both values of the absorbances and concentrations were found, the values were then graphed in order to obtain the equation of the relationship between absorbance and concentration.

You find a sample of a solution that has a faint odor resembling vinegar. You are verifying that it is indeed vinegar and you add a few drops of phenolphthalein. The sample turns pink. What assumptions can you make about this sample?

When the tip of the rod touched the pH paper, the color of the pH paper became blue.

In order to find the pH of each household item by using pH paper, the pH paper was placed on the drop plate. Using the dropper, start by having the household item dropped onto the pH paper. Immediately observe in order to spot any colour changes on the pH paper. To determine the pH by using the pH scale and record the pH on your table of observations. Depending on what the pH is, it could be very acidic, basic or neutral. Repeat these steps for the other products.

According to the BMI for Erin’s height and weight, she is considered to be under weight. A healthy weight for Erin is between 125 lbs. to 158 lbs. The recommended intake of protein for adults is 0.85 grams per kilogram of healthy body weight per day. Based on Erin’s weight, she should be consuming 43 grams of protein. Erin has been calculating her recommended dietary allowance based on an unhealthy weight and not the midpoint of the healthy weight range, which is 141 lbs. Erin’s recommended daily protein requirement should be 51grams.

4. We observed the test tubes and compared the colors produced from the reaction to the color palette in 1 minute intervals for 5 minutes total.

The mixture might have contained more or less than 5 drops of bromophenol blue, which might have resulted in the indication of the lab.

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.

Blue #1: Blue number one can be known as Brilliant Blue FCF can be traced to pesticide formulations applied to growing crops or

In the beginning of the whole heating process the water starts to leave the hydrate letting the hydrate turn a lighter blue color.

Seven clean 100 mL volumetric flasks were obtained and 2.00 mL of 1.551 ×10^(-3) M bromothymol blue was added to the 7 flasks via volumetric pipet. Other reagents including K2HPO4, NaHPO4 and NaOH were added though volumetric pipets as instructed in the table below:

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