Consider the titration of 25.0 mL of 0.0500 M Sn2+ with 0.100 M Fe3+ in 1 M HCl to give Fe2+ and Sn4+, using a Pt and calomel electrodes. (a) write a balanced titration reaction (b) write two half-reactions fo the indicator electrode (c) write two Nerst equations for the cell voltage (d) calculate E at the following volumes of Fe3+: 1.0, 12.5, 24.0, 25.0, 26.0, and 30.0 mL. Sketch the titration curve.
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When a 7.00-g sample of RbBr is dissolved in water in a calorimeter that has a total heat capacity of 3.090 kJ·K–1, the temperature decreases by 0.300 K. Calculate the molar heat of solution of RbBr.
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What is percent yield fro your synthseis of octyl acetate (acetic anhydride and 1-octanol)? V of ctyl acetate is 1.53 mL.
3 mL of acetic anhydride and 2 mL 1-octanol. One drop of concentrated sulfuric acid.
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A student dissolved 10.5 g of NH4Cl in 40 mL of water. The temperature of the water changed from 22.5oC to 5.1oC. Calculate the enthalpy of hydration of ammonium chloride in J/mol.
1. A student collected the data below while performing a kinetics experiment.
Trial |
Volume of 2.0 M Reactant A |
Volume of 0.5 M Reactant B |
Volume of H2O |
Time for B to react |
1 |
10 mL |
10 mL |
30 mL |
135 sec |
2 |
20 mL |
10 mL |
20 mL |
69 sec |
3 |
10 mL |
20 mL |
20 mL |
34 sec |
Use the above information to complete the following table (enter all answers with 3 significant figures)
Trial |
concentration of A |
concentration of B |
Rate for B |
1 |
|||
2 |
|||
3 |
Using the data from the previous problem, determine the order with respect to Substance A. Using the data from Problem 1, determine the order with respect to Substance B. Using the information from Trial 1 and the experimentally determined rate law, determine the value of the rate constant, k for this experiment. Report your answer with 3 significant figures.
Please answer all the questions and with the three significant digits after decimals. Please.
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Preparing Buffer Solutions: Calculating the Number of Grams of
Conjugate Base Needed
Use the table of K values given with this problem to choose the
best weak acid to start from for making a buffer that holds the pH
of the solution at 3.20. Make your selection so that you maximize
the capacity of the buffer.
You select a 200.0 ml volumetric flask to which you add 54.00 mL of
a 2.90 M solution of the weak acid you just selected. To finish
preparing your buffer you must now add the sodium salt of the
conjugate base. How many grams of the sodium salt of your conjugate
base must you add so that when you finally fill the flask to the
mark with deionized water the buffer will have a pH of 3.20.
Weak Acid | Ka |
CH3COOH (Acetic Acid) | 1.8 X 10-5 |
C6H5COOH (Benzoic Acid) | 6.5 X 10-5 |
CH3CH2CH2COOH (Butanoic Acid) | 1.5 X 10-5 |
HCOOH (Formic Acid) | 1.8 X 10-4 |
HBrO (Hypobromous Acid) | 2.8 X 10-9 |
HNO2 (Nitrous Acid) | 4.6 X 10-4 |
HClO (Hypochlorous Acid) | 2.9 X 10-8 |
CH3CH2COOH (Propanoic Acid) | 1.3 X 10-5 |
HCN (Hydrocyanic Acid) | 4.9 X 10-10 |
I posted this question before and they got the answer of 8.00g which is NOT CORRECT, so I was looking someone else to help me with this.
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In my lab we found OUR average molarity to be 0.83334 M, but we used 3% H2O2 (hydrogen peroxide), so I'm not sure how to do this or what numbers to even use.
7. Convert the average molarity of hydrogen peroxide into % (wt) of hydrogen peroxide (the density of the solution = 1.009g/ml).
8. Comparing the above calculated % of hydrogen peroxide with the known (labeled on the bottle) value, calculate the % experimental error.
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The first four peaks in the X-ray powder diffraction pattern of sodalite are at 2 values of 9.97°, 14.12°, 17.32° and 20.02°. The radiation used for the experiment was Cu K with = 1.5418 Å. Determine the lattice type and calculate the length, a, of the cubic unit-cell.
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FeS can be roasted in O 2 to form FeO, according to the reaction 2FeS + 3O 2 2FeO + 2SO 2 If the slag (solid product) contains 80% FeO and 20% FeS , and the exit gas is 100% SO 2 , determine the extent of reaction and the initial moles of FeS. Use 100 lb as the basis. [0.557; 1.341 lb-mol]
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A sample is analyzed to determine its iron content Fe2+ via a redox titration with potassium chromate as the titrant. In the titration Fe2+ is oxidized to Fe3+ and CrO4 2- is reduced to Cr 3+. What is the percent by mass of iron in the sample if 0.9087g of the sample required 45.68mL of a 0.04322 M K2CrO4 solution to reach the endpoint?
I worked out the balanced equation to be:
8H+ + 3Fe2+ + CrO4 2- = 3Fe3+ + Cr3+ + 4H2O
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What is the mechanism by which solute is dissolved in non polar solvents? Explain briefly. (5 mark)
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In: Chemistry
Part B What mass of carbon dioxide is produced from the complete combustion of 6.90×10−3 g of methane? Express your answer with the appropriate units.
Part C What mass of water is produced from the complete combustion of 6.90×10−3 g of methane? Express your answer with the appropriate units. Part D What mass of oxygen is needed for the complete combustion of 6.90×10−3 g of methane? Express your answer with the appropriate units
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The equilibrium constant for the reaction of fluorine gas with bromine gas at 300 K is 54.7 and the reaction is: Br2(g) + F2(g) ⇔ 2 BrF(g) What is the equilibrium concentration of fluorine if the initial concentrations of bromine and fluorine were 0.121 moles/liter in a sealed container and no product was present initially?
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In each pair, indicate which substance has the stronger intermolecular forces and explain your reasoning: (a) Ne, Ar; (b) NF3, BF3; (c) SiH4, GeH4; (d) NaF, HF.
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1. Calculate the dilution factor and final concentration of the following target analytes:
20 mL of target analyte (2.5 M), to a final volume of 100 mL
2 mL of target analyte (3.23 ppm), to a final volume of 0.05 L.
5 mL of target analyte (15.9032 %), to a final volume of 1 dL.
1 dL of target analyte (4.0989 M), to a final volume of 0.25 L
0.025 L of target analyte (1.8982 g / L), to 79 g of ethanol.
10 mL of target analyte (2.0902 g / L), to 66.5 g of dichloromethane.
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