a.) Proteins A and B with molecular weight of 16,500 and 35,400 move 4.60 cm and 1.30 cm respectively, during electrophoresis and in SDS-polyacrylamide gel. What is the molecular weight of protein C that moves 2.80 cm under the same conditions in the same gel?
b.) The sedimentation coefficient of a DNA molecule is 22.0 S. A dilute solution of the DNA is spun in a centrifuge at 40,000 rpm starting from a distance of 6.0 cm from the axis of rotation. How far will the DNA move in 20 min?
In: Chemistry
Calculate the mass of methane that must be burned to provide enough heat to convert 300.0 g of water at 30.0°C into steam at 106.0°C.
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50mL of 0.010M NaOH were titrated with 0.50M HCl, added with a dropper pipet. If each drop has a volume of 0.040mL, calculate how many drops of HCl are needed to reach the end-point of the titration.
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The vaporization of compound A is described by the given chemical equation.
A(l)⟶A(g)ΔHvap∘=42.69 kJ/mol
Calculate the entropy of vaporization, ΔSvap , for A(l) at 25.0 °C given that the boiling point of A is 78.99 °C , and the molar heat capacity of A(l) is 118.41 J/(mol⋅K) . Assume that the molar heat capacity of A(g) is 53.7% of that of A(l) .
ΔSvap=
J⋅mol−1⋅K−1
Calculate the standard Gibbs free energy of vaporization, ΔG∘vap , at 25.0 °C .
ΔG∘vap=
kJ/mol
Determine the equilibrium constant, K , for the vaporization at 181.0 °C.
K=
Determine the temperature at which the vaporization of A(l) becomes spontaneous. Assume that the enthalpy and entropy of vaporization change very little with temperature.
T=
°C
Is the vaporization of A(l) spontaneous at temperatures greater than or less than T?
less than T
greater than T
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34.62 g of ferrous bromide reacts with 29.25 g of potassium chloride in a heated vessel. Write a balanced chemical equation for this double replacement reaction. What is the percent yield of ferrous chloride if the actual yield is 10.25 g? How much excess remains?
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Balance the following equation in acidic solution using the lowest possible integers and give the coefficient of water. Cl2(aq) + S2O32- (aq) → Cl-(aq) + SO42-(aq)
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use dimensional analysis to solve the following:
a) 789mmHg to atm
b)4.11 tons to Kg
c)6.87 quart to ml
2) A mixture is found to contain 3.17g of SiO2(sand), 6.01g of cellulose, and 7.32 g of calcium carbonate.what is the mass percentage of SiO2 in the mixture? please show a detail explanation.
d) 2.98x 10 to (the fifth power ) yard to Km
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In: Chemistry
Based off these compounds, which one is the most hazardous and why?
Methyl Benzoate
Acetanilide
Nitric Acid (70%)
Acetic acid
Sulfuric Acid (98%)
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The stopcock connecting a 1.00 L bulb containing helium gas at a pressure of 554 torr, and a 1.00 L bulb containing krypton gas at a pressure of 504 torr, is opened and the gases are allowed to mix. Assuming that the temperature remains constant, the final pressure in the system is ____torr
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The binding energy per nucleon for magnesium-27 is 1.326*10-12 J/nucleon. Calculate the atomic mass of magnesium-27, in amu. You may assume that the mass of a nucleon is 1.008 amu. (1 kg = 6.022*1026 amu)
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Consider an amphoteric hydroxide, M(OH)2(s), where M is a generic metal. M(0H)2 yields M+2OH M(OH)2 +2OH yields (M(OH4)2- Ksp=3x10^-16 Kf= .05 Estimate the solubility of M(OH)2 in a solution buffered at pH = 7.0, 10.0, and 14.0.
In: Chemistry
In: Chemistry
Draw structural formulas for all possible isomers having the following molecular formulas:
a. C4H10
b. C2HBr3
c. C3H6O
d. C3H4
Please explain also if you can. Thanks!
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The reversible chemical reaction
A+B?C+D
has the following equilibrium constant:
Kc=[C][D][A][B]=3.4
Part A
Initially, only A and B are present, each at 2.00 M. What is the final concentration of A once equilibrium is reached?
Part B
What is the final concentration of D at equilibrium if the initial concentrations are[A] = 1.00M and [B] = 2.00M ?
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