CH4 + O2-----CO2 +2H2O suppose 2.8 mol methane is allowed to react with 3 mol of oxygen A) what is the limiting reactant? B) how many moles of CO2 can be made from this mixture? How many grams of CO2?

Describe how the solvents worked as the mobile phase of the liquid chromatography experiment. Why was it necessary to use different concentrations of aqueous isopropanol in the step-gradient separation?

A solution is prepared from 4.5750 g of magnesium chloride and 43.248 g of water. The vapor pressure of water above this solution is found to be 0.3626 atm at 348.0 K. The vapor pressure of pure water at this temperature is 0.3804 atm. Part A Find the value of the van't Hoff factor i for magnesium chloride in this solution. Express your answer using four significant figures.

Assuming the water sample has a pH of 7.2, determine the amount of HOCl and OCl- in mg/L contained in the free chlorine residual of the treated sample.

A 26.9 mL sample of 0.373 M triethylamine, (C₂H₅)₃N, is titrated with 0.310 M hydroiodic acid.

The pH before the addition of any hydroiodic acid is .  

Use the Tables link in the References for any equilibrium constants that are required.

A 20.6 mL sample of 0.337 M ammonia, NH₃, is titrated with 0.229 M hydrochloric acid.

At the equivalence point, the pH is .

Glycolysis

1)describe the Schiff-base role in aldolase

2)Describe the role of the thioester intermediate in G3P dehydrogenase

3) Describe the differences between glucokinase and hexokinase

4) Describe the reactants/products/regulation for the three irreversible reactions in glycolysis (1, 3, 10)

Part A

Consider the second-order reaction:

2HI(g)→H2(g)+I2(g)

Rate law: k[H]^2

k= 6.4*10^-9 (mol*s) at 500 K

Initial rate = 1.6 * 10^-7 mol (l*s)

What will be the concentration of HI after t = 3.65×10¹⁰ s ([HI]t) for a reaction starting under this condition?

Part B

In a study of the decomposition of the compound X via the reaction

X(g)⇌Y(g)+Z(g)

the following concentration-time data were collected:

Given that the rate constant for the decomposition of hypothetical compound X from part A is 1.60 M−1⋅min−1, calculate the concentration of X after 14.0 min .

Part C

The following data were collected for the rate of disappearance of NO in the reaction 2NO(g)+O2(g)→2NO2(g):

What is the rate of disappearance of NO when [NO]= 6.15×10⁻² M and [O2]=1.75×10⁻² M ?

Part D

What is the rate of disappearance of O2 at the concentrations given in part (c)?

Part E

A certain reaction with an activation energy of 175 kJ/mol was run at 515 K and again at 535 K . What is the ratio of f at the higher temperature to f at the lower temperature?

Use f=e^−Ea/(R⋅T)

A) A 52.0-mL volume of 0.35 M CH3COOH (Ka=1.8×10−5) is titrated with 0.40 MM NaOH. Calculate the pH after the addition of 17.0 mL of NaOH.

B) Calculate the molar solubility of lead thiocyanate in 1.00 M KSCN. Lead thiocyanate, Pb(SCN)2 has a Ksp value of 2.00×10−5.

C) Calculate the molar solubility of AgBr in 0.10 M NaBr solution.

D) Calculate the molar solubility of Ni(OH)2Ni(OH)2 when buffered at pH=pH= 10.2. The Ksp of nickel hydroxide =6.0×10−16 M

A 1.38 L buffer solution consists of 0.193M butanoic acid and 0.350 M sodium butanoate. Calculate the pH of the solution following the addition of 0.0680 of NaOH. Assume that any contribution of the NaOH to the volume of the solution is negligible. The Ka of butanoic acid is 1.52×10−5.

Determine the limiting reagent and calculate the theoretical yield if 0.96 g of benzyltriphenylphosphonium chloride is reacted with 0.30 mL of cinnamaldehyde.  

This is from an experiment simulating a breathalyzer. Potassium dichromate standard is 0.625 mg/mL in 9M sulfuric acid. We are using the equation 3 C2H5OH + 2 K2Cr2O7 + 8 H2SO4 → 3 CH3COOH + 2 Cr2(SO4)3 + 2 K2SO4 + 11 H2O for the reaction of dichromate and ethanol.

Operating wavelength : 436 nm
Absorbance of solution 1 (10.0 mL Standard Dichromate and 1.00 mL H₂O) : 0.577 a.u.
Absorbance of solution 2 (10.0 mL Standard Dichromate and 1.00 mL ethanol standard) : 0.445 a.u.
Absorbance of solution 3 (10.00 mL Standard Dichromate and 1.00 mL simulated ethanol DWI sample) : 0.438 a.u.
Mass of dichromate in Solution 1 : 6.25 mg
Mass of dichromate in Solution 2: 4.820 mg
Mass of dichromate in Solution 3: 4.744 mg

For solutions 2 and 3, what is the mass of dichromate consumed, the moles of dichromate consumed, the moles of ethanol consumed, and the mass of ethanol consumed?

What is the purpose of sulfuric acid, hydroxylamine hydrochloride and sodium acetate in 1, 10-phenanthroline determination of total iron? Also provide the balanced equation for hydroxylamine hydrochloride in this experiment. (NH₄)₂Fe(SO₄)₂・6H₂O is given. Sulfuric acid is used in dissolving the (NH₄)₂Fe(SO₄)₂・6H₂O and after diluted (NH₄)₂Fe(SO₄)₂・6H₂O is taken for specific volume and other two is added to the specific volume of taken diluted (NH₄)₂Fe(SO₄)₂・6H₂O solution.

Draw the Lewis structure of AsO43– showing all lone pairs. Identify the molecular geometry of AsO43–. What is the hybridization of the central As atom? What are the approximate bond angles in AsO43–? An AsO43– ion is polar or non polar?

How many GRAMS of carbon are present in 4.00 moles of carbon dioxide, CO2?

How many MOLES of oxygen are present in 3.11 grams of carbon dioxide?

How many GRAMS of oxygen are present in 9.82×10^22 molecules of tetraphosphorus decaoxide?

Partial Pressure Question

A. A mixture of krypton and oxygen gases, in a 9.68 L flask at 34 °C, contains 8.73 grams of krypton and 8.09 grams of oxygen. The partial pressure of oxygen in the flask is ___ atm and the total pressure in the flask is___ atm.

B.A mixture of argon and helium gases is maintained in a 9.06 L flask at a pressure of 2.61 atm and a temperature of 71 °C. If the gas mixture contains 9.81 grams of argon, the number of grams of helium in the mixture is ___g.

C. A mixture of krypton and oxygen gases, at a total pressure of 649 mm Hg, contains 8.03 grams of krypton and 7.43 grams of oxygen. What is the partial pressure of each gas in the mixture?

P_Kr = __mm Hg
P_O2 = __mm Hg

D. A mixture of argon and helium gases contains argon at a partial pressure of 238 mm Hg and helium at a partial pressure of 575 mm Hg. What is the mole fraction of each gas in the mixture?

X_Ar = __
X_He =__