Calculate the pH of a 0.368 M solution of ethylenediamine (H2NCH2CH2NH2). The pKa values for the acidic form of ethylenediamine ( H3NCH2CH2NH3 ) are 6.848 (pKa1) and 9.928 (pKa2). Calculate the concentration of each form of ethylenediamine in this solution at equilibrium.
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How many acetyl CoA molecules are formed when 1 molecule of myristic acid (14:0) is broken down?
| 14 |
| 6 |
| 7 |
| 8 |
| 28 |
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5. According to your experimental results, how much vitamin C would you get from a 4 oz. (120 mL) serving of fresh orange juice?
a. Less than the RDA.
b. More than the RDA.
c. Almost exactly the RDA.
Explain your answer:
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Please show all work and derivations
A "barrel of oil" in international trade has a volume of 42 US gallons, or 159 L. How much heat would be released if 159 L of pure n-octane (C8H18) was burned completely at constant pressure, and with products and reactant at 298 K. The standard enthalpy of combustion of n-octane is -5471 kJ/mol and its density is 0.703 g/cm^3.
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A compound has an M+ ion at 102 amu. There is no M+2 peak. The only IR absorbances in the interpretable region are at 3500 and 2900 cm−1. The 13C NMR spectrum shows three resonances at δ 70 (d), 35 (t), and 30 (t). Draw a structure consistent with this information.
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1. Exercise 11.79
A gas mixture contains 74% nitrogen and 26% oxygen.
If the total pressure is 1.18 atm what are the partial pressures of each component?
Express your answers using two significant figures. Enter your answers numerically separated by a comma.
2. Chapter 11 Question 11 - Algorithmic
What is the molecular weight of a gas if a 21.0 g sample has a pressure of 836 mm Hg at 25.0°C in a 2.00 L flask? (R= 0.0821 L atm/ mol K)
What is the molecular weight of a gas if a 21.0 g sample has a pressure of 836 mm Hg at 25.0°C in a 2.00 L flask? (R= 0.0821 L atm/ mol K)
| 243 amu |
| 234 amu |
| 1.89 amu |
| 11.1 amu |
| none of the above |
3. Exercise 11.91
CH3OH can be synthesized by the reaction:
CO(g)+2H2(g)→CH3OH(g)
Part A
How many liters of H2 gas, measured at 748 mmHg and 83 ∘C, are required to synthesize 0.53 molof CH3OH?
|
|
||||
| VH2 = | ?????? |
L |
Part B
How many liters of CO gas, measured under the same conditions, are required?
Express your answer using two significant figures.
|
|
||||
| VCO = | ????? | L |
4. Exercise 11.97
How many grams of calcium are consumed when 160.4 mL of oxygen
gas, measured at STP, reacts with calcium according to the
following reaction?
2Ca(s)+O2(g)→2CaO(s)
|
|
||||
| mCa = | g |
In: Chemistry
In: Chemistry
Calculate the percent ionization of hypobromous acid (HBrO) in solutions of each of the following concentrations (Ka = 2.5e-09.) (a) 0.263 M (b) 0.477 M (c) 0.868 M
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prepare .1M Sodium phospahte buffer, pH 6.8. you need 500ml.
NaH2PO4-H20= 137.99g/mol
Na2HPO4-7H20= 268.08g/mol
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Consider the following gas-phase reaction: C6H6(g) 3 C2H2(g) Using data from Appendix C of your textbook calculate the temperature, To, at which this reaction will be at equilibrium under standard conditions (Go = 0) and choose whether >Go will increase, decrease, or not change with increasing temperature from the pulldown menu.
T = ____K, and G will _______
For each of the temperatures listed below calculate G for the reaction above, and select from the pulldown menu whether the reaction under standard conditions will be spontaneous, nonspontaneous, or near equilibrium ("near equilibrium" means that T is within 5 K of To).
(a) At T = 896 K G=
(b) At T = 1792 K G=
(c) At T = 2688 K G=
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Properties of matter
A metal crystallises in a face-centred cubic lattice.The edge of the unit cell is 286pm,and the density of the crystal is 7.92gcm^-3.Calculate the atomic mass of the element?
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In the titration of 30.0 mL of a 0.200 M solution of a hypothetical compound NaH2M, what is the pH of the solution after the addition of 30.0 mL of 0.100 M NaOH? For H3M, pKa1 = 3.00, pKa2 = 6.00, and pKa3 = 9.00.?
The answer is 6.0 which is not what I got in my work. Please help me out !
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Compare and contrast between the ionic addition and the free fadical addition of HBr to 1-butene.
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1. mix 2.5 Ml cyclohexanone, 7.5g of KMnO4, 65 ml H2o in a round bottom flask. Use steam bath and heat to 30 degree C. 2. Add 1 ml of 3M NaOH solution, stirring with glass rod. When the temperature reach 45 degree C. slow the oxidation process by ice-cooling, and keep the temperature at 45 degree C for 30 mins. 3. Then heat the picture on heating mantle, adjust to 70V, wi reflux to complete the oxidation (55 degree C) 4. Make a spot test by withdrawing reaction mixture on the top pf the stirring rod and touching it to a filter paper. KMnO4 if present, will show purple ring around the spot. 5. Keep heating and make the spot test, unit there is no KMnO4 present. 6. Separate the solid and liquid mixture by suction filtration, rinse the brown precipitate well with water. 7. Add a boiling chip and evaporate the filtration to a volume of 17 ml. (while evaporating my cup tipped over and all of my product spilled, I only had about 3ml left.) 8. Acidify the hot solution with concentrated HCl to pH 1-2, add 5 ml acid in excess, and let the solution stand to crystallize. 9. Collect the crystals with suction filtration, rinse the solid with water. Turn on vacuum for few minutes to dry the solid completely. 10. measure the madd of the solid. and determine the melting point.
Calculate the theoretical yield of adipic acid.
What is the limiting reagent in this reaction? Why do you think this reagent rather than the other made limiting?
Why does acidification of the concentrated reaction mixture cause precipitation of adipic acid?
Why does the initially purple solution of KMnO4 change color as the oxidation progresses?
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