An industrial chemist introduces 6.8 atm H2 and 6.8 atm CO2 into a 1.00-L container at 25.0°C and then raises the temperature to 700.0°C, at which Keq = 0.534: H2(g) + CO2(g) ⇔ H2O(g) + CO(g) How many grams of H2 are present after equilibrium is established?
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A sample of a gas mixture contains the following quantities of three gases.
| compound | mass |
|---|---|
| CO | 2.68 g |
| CO2 | 3.69 g |
| SF6 | 2.13 g |
The sample has:
volume = 2.50 L
temperature = 16.6 °C
What is the partial pressure for each gas, in mmHg?
What is the total pressure in the flask?
CO ___ mmhg
CO2 __mmhg
SF6 ____ mmHg
total ___ mmHg
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A) 1 L of solution contains 0.10 mol Ag+ and 0.10 mol of Ba2+. If a highly concentrated solution of K2CrO4 is added drop by drop, which will precipitate first, Ag2CrO4 or BaCrO4?
Ksp for AgCrO4 = 2.0 x 10^-12; Ksp for BaCrO4= 1.2 x 10^-10
B) If the solution in part "A" contains 0.0010 Ag+ and 0.0010 mol of Ba2+ instead, which will precipiate first, Ag2CrO4 or BaCrO4?
Answers: A) Ag2CrO4 and B) BaCrO4
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Plamitate uniformly labeled with tritium (3H) to a specific radioactivity of 3.0×·10^8 counts per minute per micromole was added to a mitochondrial preparation that oxidized 3H-palmitate to acetyl-CoA. The experiment calls for hydrolysis of the recovered acetyl-CoA to acetate and determination of the specific radioactivity of the acetate in counts per minute per micromole (cpm/μmol). Assuming that the palmitate is oxidized by the β-oxidation pathway and that there is no unlabeled fatty acid to dilute the tritium, what would be the expected specific radioactivity of the acetate? Show your reasoning and calculations.
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Column Chromatography Lab
1. What would happen if diethyl ether were put in the column first instead of petroleum ether?
2. The recrystallization lab required you to purify naphthalene which contained a small portion of fluorenone. Could you use column chromatography to purify the same mixture? Would the selection of solvents be different from those used in this lab?
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A 0.500 M solution of a weak base has a pH of 9.00. What is the base hydrolysis constant, Kb, for the weak base?
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Calculate the pH for the titration 20.00mL of 0.500M HF with 0.500M KOH at the following volumes of added titrant:
a) 0.00 mL (before titration begins)
b)10.00mL (at 50% equivalence)
c) 19.00 mL (at 95% equivalence)
d) 20.00 mL (at equivalence point)
e) 21 mL (at 105% equivalence)
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Write the balanced molecular equation for any reaction that occurs when the following solutions are mixed.
1. Ba(C2H3O2)2 and Na2SO4
2. NaClO4 and Pb(NO3)2
3. Mg(NO3)2 and Na3PO4
4. SrS and NiI2 (thats Nickel and Iodide)
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Explain how to find the concnetration of an unknown when the when five reference have a mixture of five different compounds. by internal standard method
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An electron in the n = 5 level of an H atom emits a photon of wavelength 4052.28 nm. To what energy level does the electron move?
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And please show me the step by step process of how you solved the question. I have a learning disability and I need to know the steps to solve the question
If it takes 17.5 mL of 0.085 M NaOH to titrate a 15 mL sample of sauerkraut juice, what is the acidity of that juice, expressed as % lactic acid (wt/vol)?
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How many milliliters of an aqueous solution of 0.212 M copper(II) chloride is needed to obtain 6.74 grams of the salt?
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Ethanol can be synthesized by direct hydration of ethylene: C2H4(g) + H2O(g) ----> C2H5OH(g). at t = 300degC and P = 60 atm. Calculate the yield of the rxn for conditions as above and the equimolar (1:1) input mixture. Use following data: DfH298 (KJ mol-1): C2H4 = 52.4; H20 = -241.8; C2H5OH = -234.8. DfG298 (Kj mol-1): C2H4 = 68.4; H20 = -228.6; C2H5OH = -167.9
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The van der Waals equation for 1 mole of gas is given by (p
+av-2)(v - b) = RT. In general, curves of p versus v
forvarious values of T exhibit a maximum and a minimum at the
twopoints where (δp/δv)T = 0. The maximum and minumum
coalesceinto a single point on that curve
where(δ2p/δv2)T = 0 inaddition to
(δp/δv)T = 0. This point is calledthe "critical point"
of the substance and its temperature,pressure, and molar volume are
denoted by Tc,pc, and vc,
respectively.
(a) Express a and b in terms of Tcand
vc.
(b) Express pc in terms
ofTc and vc.
(c) Write the van der Waals equation in terms
ofthe reduced dimensionless variables T' ≡ T/Tc , v'≡
v/vc , p' ≡ p/pc
This form should involve neither a nor b.
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1. What is the difference between the heat of reaction, Qrxn, and the enthalpy of reaction, Hrxn? (
2. In a coffee-cup calorimeter, 1.40 g of NH4NO3 is mixed with 71.0 g of water at an initial temperature of 25.00 oC. After dissolution of the salt, the final temperature of the calorimeter content is 23.39 oC. Assuming the solution has a heat capacity (Cp) of 4.18 J/ oC•g and assuming no heat loss to the calorimeter (surroundings), calculate the enthalpy change for the dissolution of NH4NO3 in units of kJ/mol. (MW(NH4NO3) = 80.05 g/mol)
3. How do cold packs and hot packs work? What kind of thermodynamic process is involved in a hot pack?
4. Who uses hot packs and cold packs? What kind of process is involved in a cold pack?
5. What is the chemical that is used in hot packs that use a super cooled fluid? Why is that chemical a good choice for use to manufacture a hot pack?
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