PLEASE SEE FILES ATTATCHED FOR THE CHEM QUESTIONS BELOW:
2. (a) Using the 60-second absorbance graphical data (see attached Exp 6 Trial 1 LoggerPro graph), what is the rate constant, k, for Trial 1 ?
3. Answer the following questions that explains the thermodynamics of KNO3 dissolving in water:
PLEASE JUST ONE PAGE FOR ALL QUESTIONS BRIEF.
(a) What happens to the temperature at saturation point of KNO3 as the volume of solution increases? Briefly explain.
(b) Is the process spontaneous or non-spontaneous? Briefly explain.
(c) Is the dissolution process exothermic or endothermic? Briefly explain.
(b) Using the data from Trials 1 to 4, calculate the activation energy (Ea) in kJ /mol for the crystal violet and sodium hydroxide reaction. (R = 8.314 J/K mol) (Attached the graph and calculations)
4.
(a) locate and name the positive electrode.
(b) locate and name the negative electrode.
(c) identify (name and chemical formula) the chemical used in the salt bridge.
(d) write the half –cell reactions and the overall reaction.
5. Given the following equilibrium concentrations for the reaction at 23 oC in this experiment:
[Fe+3] = 9.84 x 10-4 M
[SCN-] = 1.84 x 10-4 M
[FeSCN2+] = 0.156 x 10-4 M
(a) Write the balanced net equation of the reaction.
(b) Write the equilibrium expression or equation of the reaction.
(c) Describe the evidence of chemical reaction.
(d) Why is Beer’s law used in determining the concentration of the product formed in the reaction?
(e) Calculate the equilibrium constant, Keq, of the reaction.
(f) Is the reaction product favored or reactant favored? Briefly explain your answer.
6. a) identify the hazard classification (e.g. health hazard, acute toxicity, flammable, corrosive, oxidizer, irritant, etc.) of pictogram A and B, and
b) give an example of a reagent that you studied in the lab that used this pictogram A and B to warn the user about its hazard.
7.
(a) What is the calculated Heat of Vaporization of methanol in kJ/mol (R = 8.314 J mol-1 K-1) ?
(b) What is the percent error (theoretical value from PubChem is 37.34 kJ/mole at 25 oC)?
(c) Give at least one reason for the cause of the high or low percent error.
