Consider the following reversible chemical reaction. Imagine that you have prepared a solution of FeSCN2+ which is initially blood red in color. Answer the following questions about the equilibrium shifts and color changes that result from various chemical changes.
Fe3+ (aq) + SCN-(aq) FeSCN2+(ag)
1
..t
yellow
colorless blood red
1. First, several drops of concentrated iron nitrate (Fe(NO3)3) are added to the red solution. As a result, the solution will
turn darker red
2. You know that the iron(II) ions (Fe3+) will combine with chloride ions (Cl) to form an insoluble salt (FeCl3) that precipitates out of solution. If you
add a scoop of sodium chloride (NaCl) to the solution, it will turn lighter red/orange
3. Now a milliliter of concentrated potassium nitrate (KSCN) solution is added to the solution, making it not change color
4. You know that silver ions (Ag) will combine with thiocyanate ions (SCN) to form an insoluble salt (AgSCN) that precipitates out of solution. If you
add silver ions to this solution, it will turn darker red
V
5. You also know that this is an endothermic reaction. If you heat this solution to raise the temperature, it will
QUESTION 5

13. calculate the initial concentration (before precipitation) of carbonate ions after the addition of each 0.05 ml of solution b to the 1.00 l beaker of solution a. divide the work among group members and write the answers in the table in model 3. assume the volume change as solution b is added is negligible. 14. notice the initial concentrations of zn2+ - and cu2+ in the table in model 3. a. explain how these were obtained from the data in model 2. b. as solution b is added and precipitates form, do these initial concentrations change? 15. use the data in model 2 to indicate the presence of precipitate (either znco3 or cuco3) after each 0.05 ml addition of solution b in model 3. 16. use the initial concentrations of carbonate ions and zinc ions to calculate the reaction quotient, qsp for the zinc carbonate scenarios in model 3. divide the work among group members and write the answers in the table in model 3. 17. use the initial concentrations of carbonate ion and copper(ii) ions to calculate the qsp for the copper(ii) carbonate scenarios in model 3. divide the work among group members and write the answers in the table in model 3.

Since the gas in your graduated cylinder is a mixture of butane and water vapor, you must determine the partial pressure of the butane, pbutane, alone. to do this, consult a reference and record the partial pressure of the water vapor, pwater, at the temperature you recorded. use the following formula to compute the partial pressure of the butane. pbutane = atmosphere - pwater use the following combined gas law formula and compute the volume that the butane sample will occupy at stp. (hint: convert both temperatures to kelvin.) pbutane x voriginal = pstandard x vfinal troom tstandard use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. grams of butane you used “x” grams of butane ml of butane corrected to stp = 22,400 ml compute the theoretical molar mass of butane based on its formula and the atomic masses on the periodic table. compare your experimental results from #3 to the theoretical value of #4, computing a percent error of your findings using this formula: % error = measured value - accepted value x 100 accepted value use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. need asap

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.