One of the constants in the experiment was that the chloropyll content was measured every 48 hours.   A True   B False

If you wanted to know if your average absorbances for pH 7 and pH 11 were different, what preliminary calculation would you preform? Select one: a. Standard deviation b. Variance c. Standard error of mean d. Range

Two classes were tested to compare the class average on the final exam. Both classes were given the same final exam. One class was allowed to use their study guide on the final and the other class was not. Identify the CONTROLLED VARIABLE in the problem. 37.

Svedberg units direct correspond to molecular weight. True False

A mixture of species of A and B is injected into a liquid chromatographic column with length of 20.0 cm. The obtained separation results are listed as follows: Species Retention time (min) Peak Width at Base (min) Non-retained 3.0 A 5.2 0.48 В 5.9 0.56 From the data, the calculated resolution Rs is smaller than 1.5 for A and B when the column length is 20.0 cm, which indicates that A and B are not separate completely. What is the new column length (unit: cm) necessary to separate the A and B species with a good resolution Rs = 1.5? Please keep your answer to one decimal place.

(please type answer no write by hend).

Calculate the amount of protein (in mg) in Sample 1 if the measurement at A280 = 0.636, taking into account the dilution factor as per question 6 (100ul) and the total volume of extract as per question 4 (140ml). Give your answer as a number with no decimal places.

Sucrose + H2O(negative control): Colorless to brown solution: Blue solution Conclusion for Iodine test A. amylose present B. amylose not present Conclusion for Benedict's test A. reducing sugars not present  B. reducing sugars present  Sucrose + HCl(potential hydrolysis): unchanged compared to sucrose+water:  Conclusion for Iodine test A. more amylose present B.  LESS amylose present C. NO change  Conclusion for Benedict's test a. more reducing sugar present  b. less reducing sugar present   c. no change  Did hydrolysis of sucrose occur in the presence of acid? A. Yes  B. no

Suppose a researcher is investigating the measurement ability of a new device intended to read the freezing point of a chemical compound. The substance used in the investigation has a known freezing point of -24 degrees Celsius. The researcher conducted a series of 10 sample measurements of the freezing point, and the results are represented below. What can we say about the device with regards to its precision, and potential bias?   Measurement Freezing Point (degrees Celsius) 1 -26 2 -18 3 -32 4 -31 5 -24 6 -24 7 -24 8 -24 9 -11 10 -37

We can assume that you did not make any calculation errors, bu error in the field can be problematic. what sources of error in the field may be have affect the data?