You are a CEM 262 TA and are preparing a 1.97 M ZnCl2 solution as an unknown for the EDTA titration experiment. The pH must be below what value to avoid precipitation of zinc hydroxide in the solution? The solubility product of Zn(OH)2 is 3×10-16. For this calculation, assume that the solution is ideal.
In: Chemistry
Consider a binomial experiment. If the number of trials is increased, what happens to the expected value, if the number of trials is decreased, what effect would occur? With regard to the standard deviation, illustrate how and why the larger the deviation number, the more difficult it would be to predict an outcome. Use specific examples to illustrate.
In: Statistics and Probability
Foil Plates
Place foil plates on the Van de Graaf generator face down. When the generator is on, what happens to the plates? Repeat the experiment with the plates facing up. Do plates behave any different? If so, why? If not, why not? Explain your reasoning.
Please draw picture
In: Mechanical Engineering
Consider an experiment in which we bombard an unknown, quantum system with a broad beam of monochromatic light. By varying the frequency of the light, we detect which frequencies are absorbed by the system and which pass through. What characteristics do those frequencies exhibit if our system is a simple harmonic oscillator?
In: Physics
write a short report to the president of your company about a test you conducted on one of the following:
Include the purpose, procedures, results, conclusions, and recommendations of the experiment.
Optional - Include visuals if it will enhance your presentation and help you explain your information better
In: Economics
A researcher wants to find out whether the compound NAD+ can act as an anti-aging pill.
a. What would the control group for this experiment be?
b. What is the purpose of a control group?
c. Paid volunteers are to be randomly assigned into either the treatment or control groups. What is the purpose of the random assignment?
In: Statistics and Probability
Describe Zajonc's drive theory of social facilitation. Then, describe the role of implicit processes in romantic relationships. Explain the relationship between wealth and happiness. What were the findings in the Zajonc’s experiment measuring both private and public attitudes in a sexual harassment suit? What was encouraging about the study results?
In: Psychology
what does testing a mutant virus versus a wildtype virus tell you in an experiment? can you provide an example figure of western blot and give explanation as to what I'm looking at? why would a researcher mutate the bacteria of which the virus infects? What would that tell you?
In: Biology
TLC analysis of an unknown sample using pure ethyl acetate as a developing solvent gives a single spot with an Rf value of 0.08.
A. Explain why this result doesn't guarantee that the sample is a pure compound.
B. Suggest two changes that could be made to the experiment to improve the analysis of the unkonwn sample.
In: Chemistry
The anthocyanin in hydrangeas can be isolated and used as an environmentally friendly pH indicator for titrations. At the end of a titration reaction of a strong acid with a strong base, you have a neutral solution. What color do you expect anthocyanin to be at the end of a titration? Describe a lab experiment to support your prediction.
In: Chemistry