Calculate the equivalence point potential for the titration of ferrous ion with dichromate ion in H2SO4
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Show the complete mechanism for the acid-catalyzed reaction of acetaldehyde with ethanol to form an acetal.
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Freezing point depression can be used to experimentally determine the van't Hoff factor of a solute in solution. Given the data in the table, please answer the questions below and determine the "real" van't Hoff factor of the solute.
Experimental Results
| Mass of solvent (water) | 5.267 g |
| Freezing point of water | 0.00°C |
| Freezing point depression constant (Kf) of water | 1.86°C/m |
| Mass of solution | 6.121 g |
| Freezing point of solution | -3.73°C |
a. What mass of solute was used?
b. What is the freezing point depression, ΔTf, of the solution?
c. What is the colligative molality, mc, of the solution?
d. How many moles of solute particles are present in solution?
e. If the solute has a molar mass of 235.28, what is the van't Hoff factor, i, for the solute? (Remember that experimentally, i does not have to be an integer!)
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Given the following solubilities in grams/100ml of water (these are the amounts that stay in solution at these temperatures):
caffeine 1.35g (16 degrees Celcius) 45.5g (65 degrees celcius)
NaCl 35.7g (0 degree celcius) 39.1g (100 degrees celcius)
Suppose that 20g of a mixture that is 75% caffeine and 25% NaCl is crystallized from 100mL of boiling water and cooled to 16 degrees celcius.
a) how much of the caffeine from this mixture stays in solution at 16 degrees celcius?
b) what is the most caffeine from this mixture that can be expected to cystallize?
c) How much NaCl from the original mixture stays in solution?
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If you start with 3.0×10^10 I−131 atoms, how many are left after approximately 1month? I−131 has a half-life of 8.0 days. Express your answer using two significant figures.
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An unidentified covalent molecular compound contains only carbon, hydrogen, and oxygen. When 7.40 mg of this compound is burned, 21.98 mg of CO2 and 3.00 mg of H2O are produced. The freezing point of camphor is lowered by 10.4
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Draw an example of an octahedral complex that takes part in a ligand to metal charge transfer.
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I have a few questions relating to ph and whatnot..
1) Calculate the pH of 0.0010 M Ca(OH)2 solution. (to 2 decimal places)
2) Determine the pH of a KOH solution made by mixing 0.251 g KOH with enough water to make 1.00 � 102 mL of solution.
3) Calculate the pH of 0.0171 butanoic acid, Ka=1.52 x 10-5. Answer in 4 significant figures.
4) Calculate the pH of 0.00000M C5H5N solution. Kb=1.5 x 10-9. Answer in 3 decimal places.
5) Calculate the pKa of a 0.080M HOCl solution with a pH of 3.22.
6) A solution containing NH3(aq) and NH4Cl(aq) has a pH of 9.5. What is the [NH3]/[NH4+] ratio in this solution? For ammonia, Kb = 1.8 � 10�5.
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A solution contains 12.00 g of unknown compound (non-electrolyte) dissolved in 50.0 mL of water. (Assume a density of 1.00 g/mL for water.) The freezing point of the solution is -4.95 ∘C. The mass percent composition of the compound is 53.31% C, 11.19% H, and the rest is O. Part A What is the molecular formula of the compound? Express your answer as a molecular formula.
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The parameter g varies with temperature for molecular gases because of the varying contributions from molecular vibrations. Determine g in the low-temperature and the high- temperature limits for (a) CO2 (g) and (b) H2O (g).
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At 650 K, the reaction MgCO3(s)<->MgO(s)+CO2(g) has Kp=0.026. A 10.1L container at 650 K has 1.0g of MgO(s) and CO2 at P = 0.0260 atm. The container is then compressed to a volume of0.500L . Find the mass of MgCO3 that is formed.
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What percentage reduction in carbon emissions do the following natural gas-fired CHP systems provide compared to the specified separately generated electricity and heat systems? For carbon emissions, assume natural gas emits 53 g CO2/MJ, and for average grid emissions assume 0.6 kg CO 2 /kWh. The joule equivalent of 1 kWh of electricity is 3.6 MJ.
a. CHP with 36% electrical efficiency and 40% thermal efficiency versus an 85%-efficient gas boiler for heat and the above average grid for electricity.
b. CHP with 50% electrical efficiency and 20% thermal efficiency versus a 33%-efficient, 1.0 kg CO 2 /kWh, coal-fired power plant for electricity and an 80%-efficient gas-fired boiler for heat.
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If I want to make 12 g of XeO2 from the elements, how much Xe do I need, in grams
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a) If 42.1 mL of 1.02 M sodium hydroxide, measured using a graduated cylinder, is placed in a beaker filled with 300 mL of DI water, what is the concentration of the diluted NaOH solution?
b) Why does this calculation only provide an estimate of the NaOH concentration? In other words, why do we have to standardize the NaOH in this experiment to find its exact concentration? (Hint: think about the glassware
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