Start Discovering Solved Questions and Your Course Assignments
TextBooks Included
Active Tutors
Asked Questions
Answered Questions
The half-life of cesium-137 is 30yrs. Of an initial 100 g sample, explain how much cesium-137 will remain after the 300 yrs in mg?
A buffer solution is prepared by dissolving the HA and NaA in the pure water. The sum of the molarities of HA and NaA is 2.25 and the pH of the solution is 7.50.
If you were now to mix these two RNA single-strand copies together, do you think they would form a double stranded RNA molecule? Imagine you had made an RNA copy of each strand of a DNA double helix
What sequence of base pairs would dissociate most easily into single strands if the DNA duplex were heated gently, of all possible DNA nucleotide sequences.
Calculate the percentage of the enol form in neat ethyl acetoacetate? Ethyl acetoacetate is a liquid. The value of the tautomeric constant for neat ethyl acetoacetate is Kt = .079.
Nitration of the isomer with the 13 degree C mp results in only one mononitrated product. There are three xylems. Their melting points are 13 degrees C, -24 degrees C, and -48 degrees C.
Determine the numbers of moles of HI are present at equilibrium if 2.00 moles of H2 and 3.00 moles of I2are introduced into a 2.00 L flask at 500o C.
One of the nuclides in each of the following pairs is radioactive. Explain which is radioactive?
Explain what would happen to Kc values in an experiment if the Beer's law Constance (k) value used was low (e.g you used 4000/M when the actual constant had a value of 5000/M)?
Determine the concentration of the free nickel (II) ion in a solution in which the equilibrium concentration of free ethylenediamine is 0.400 molar, and that of the nickel complex above is 0.0100 mo
Determine the numbers of peaks would you expect to find in the NMR spectrum of caffeine and explain what characteristic absorption bonds would you expect to find out in the infrared spectrum of caf
Discuss how the solid-vapor equilibrium operates in this instance. To color spots on TLC plates for easier visualization after elution with solvent, the plates can be "developed" in a seale
Explain in detail. The Caffeine is soluble in ethyl acetate. Do you think that the purity of your product could be checked by TLC using ethyl acetate as an elution solvent?
Provide the list several m advantages and disadvantages of steam distillation as a method of purification. Discuss why the distillate collected from the steam distillation of cinnamon is cloudy?
Determine the weight of the water required to steam distill 500 mg of bromobenzene at the 95 degree centigrade if the vapor pressure of water at this temperature is 640 torr; that of bromobenzene i
The ortho isomer distills at 93 degree centigrade; the Para isomer does not. Explain. Steam distillation may be used to separate a mixture of p-nitro phenol and o-nitro phenol.
What weight of water is needed to steam distill 300 mg of nitrobenzene when a mixture of nitrobenzene and water steam distills at 99 degree centigrade. The vapor pressure of water at this temperatu
Determine the vapor pressure of a water solution which is having the 0.080 mole sucrose and 0.72 mole water. At a certain temperature, water has a vapor pressure of 90.0torr.
Toluene is 34.8 % by volume. What are (a) the mass percent toluene and (b) the density? At 20oC, the density of benzene is 0.879 g/mL and that of toluene is 0.866 g/mL.
Determine the percentage yield for this experiment? Give an equation with structural formulas for the major reaction and show your calculations.
What are the (a) mass percent, (b)molarity, and (c) mole percent of methanol in this solution? A 2.90 m solution of methanol (CH3OH) in water has a density of 0.984 g/mL.
Naturally-occurring boron (atomic mass = 10.8 D) is composed of two isotopes, 10B and 11B. These problems seem pretty easy, but I haven't had chemistry in over two years. Determine the fracti
After all the metal had reacted, the remaining acid required 0.0334 L of 0.500M NaOH solution for neutralization. A 1.00-g sample of a metal X (that is known to form X+2 ions) was added
Determine the mass percent of the mixture when a 1.32 g sample of C6H12 and C10H8 is dissolved in the 18.9 g of C6H6. The freezing point of the solution is 2.20 C
Determine the basic difference among the anelectrophile and a nucleophile and how can we it identify it in a reaction? Explain in detail.