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1. A solution of Na2SO4 containing 98.0 g of the salt and 850. mL of water was prepared at 25 °C. What is the mass percent of Na2SO4 in this solution? Density of water at 25 °C: 1.00 g mL–1
2. A concentrated aqueous solution of sulfuric acid (H2SO4) was diluted and the concentration determined by titration with aqueous NaOH. 12.32 mL of 0.294 mol L–1 NaOH solution wa
What is the name of the reagent in this orgo chem problem? ( picture attached)
Hello,
I've been trying to understand why this happens and how, but I've never seen this before. Also, it's hard to read the reagent. Does anyone know what it says and how the ring closes?
Do all syndets render negative of precipitates when mixed with hard water?
If there is such cases (like mine) wherein syndets resulted to what look like precipitates or bubbles in tap water or in any of the following Ca, Mg or ferric chloride solutions, what does this indicate or mean? Thanks.
Using the following data reactions: delta H° (kJ) H2(g) + F2(g) 2HF(g) –542 H2(g) -->2H(g) 432 F2(g) -->2F(g) 154 calculate the energy of an H-F bond. A) 11
Suppose you performed a distillation of a solution containing butyl alcohol (C4H10O, also known as 1-butanol), sec-butyl alcohol (C4H10O, also known as 2-butanol), and ethyl alcohol (C2H6O). Butyl alcohol and sec-butyl alcohol have the same chemical formula, but they do have a different arrangement of their atoms (i.e. they are shaped differently), so this makes them have slightly d
(20 points) Draw the titration curve for the titration of 25 mL of a 0.18 M solution of lysine (pka1 = 2.18, pKa2 = 8.95) with 0.15 M sodium hydroxide. Clearly label the axes of your graph in mL of sodium hydroxide added. Be sure to include pH values and volumes for the following: Start of the titration (no sodium hydroxide added), the pH at the volume that is half of
What did you observe when your solution of water and t-butyl alcahol was shaken with saturated potas
the salting out effect: 1)what did you observe when your solution of water and t-butyl alcahol was shaken with saturated potassium carbonate?
2)addition of pottasium carbonate _____ (decrease or increase) the solubility of t-butyl alcahol in aqueous phase. A few drops of the resultant upper layer dissolved in .5ml of the water but did not dissolve in .5 ml of saturat
Calculate the change in interaction potential in dissolving a MgCl2 salt crystal
Using magnesium chloride salt as your reference, calculate the following. Some useful information: Ionic radii: Mg2+= 86 pm, Cl- = 167 pm, liquid water dipole =2.95 D, water radius 140 pm, assume that Mg2+ and Cl– are each hydrated by 6 waters (octahedral) and assume that the εr = 1 (even though you are using water, there are no waters between the dipole and the ion, thus the v
Which of the statements listed below is true regarding the following redox reaction occurring in a ...
Which of the statements listed below is true regarding the following redox reaction occurring in a spontaneous electrochemical cell? Sn(s) + Cu2+(aq) → Cu(s) + Sn2+(aq) Question 40 options:
Sn is oxidized at the cathode.
Anions in the salt bridge flow from the Sn half-cell to the Cu half-cell.
I need help with my lab worksheet.... i have no clue to anything. its somewhat like the question asked by jellyfish on sept. 27, 2010. "overall reaction of zinc metal and tincture of iodine". But this is a continuation of it, afterwards i add in a few drops of chlorine (bleach) and now i'm supposed to find the Reaction of Iodide and Chlorine (in bleach) - OXIDAT
Design a dilution scheme to achieve the following aims. Make sure to draw the dilution scheme, include the volume of dilution blanks used, volumes transferred, and the fold dilution that corresponds to the volume transferred.
4. In order to be able to decipher protein structure on StructureSupraX2000, the protein concentration has to be in the range of 0.1-0.2 nM. Y
Given a 2mg/ml stock of BSA make 100microliters each of 400and 300 microliters/ml diluted standards in 1% triton x-100. For simplicity each diluted standard will be from the stock as opposed by serial dilution.
I'm stuck. Can someone please show me how to determine why all of the following would effectively deprotonate benzoic acid (phcooh): (i would not have access to pKa values...please show me reactions thought process)
i-PrMgBr NaOh NaH (i-Pr)2NLi
also...why would LiOCH3 Not effectively deprotonate acetylene Yet, Ch3OCH2MgBr and Ch3Li
An electron microscope employs a beam of electrons to obtain an image of an object. What energy must be imparted to each electron of the beam to obtain a wavelength of 28.0 pm? Obtain the energy in electron volts (eV). (1 eV = 1.602E-19 J, mass of electron = 9.1094E-31 kg).
Finding number of photons from wavelength and energy
The retina of the eye contains two types of light-sensitive cells: rods (responsible for night vision) and cones (responsible for color vision). Rod cells are about a hundred times more sensitive to light than cone cells and are able to detect a single photon. Suppose a group of rod cells are radiated with a pulse of light having an energy equal to 1.01E-16 J. If the wavelength of t
Medium 1099 contains coy's solution, 10% fetal bovine serum, 20mM HEPES, 10 microgram/ml insulin, 1x beta-mercapatoethanol, and 2mM glutamine.
You have the following reagents: coy's solution containing 7mM HEPES as well as stocks of 1M HEPES solution, 4mg/ml insulin, 1000x beta-mercapatoethanol, and 200 mM glutamine. How would you make the medium1099? Show and e
What is the total orbital energy of this satellite? Extra energy to put it into parabolic orbit?
A communications satellite of mass 700 kg is placed in a circular orbit of radius 4.23 X 10^7m around the Earth.
A) What is the total orbital energy of this satellite?
B) How much extra enegry would we have to give this satellite to put it into parabolic orbit that permits it to escape to infinite distance from the earth?
Of a known amount of powdered aspirin tablets, take a weight that is equivalent to 600mg aspirin add 40m1 0.5M NaOH, heat for 15 minutes, titrate the excess of alkali with standardized 0.5M HCl using phenol red solution as indicator. Calculate the percentage label claim. . knowing that Volume of the end point (volume of HC1)=30m1 Mwt of aspi
according to neutralization capacity of antiacid add to conical flask 10 ml of the standard 0.5M HCL, then Stopper the flask and let it stand at room temperature for 10 min.-Add 5-6 drops bromophenol blue then titrate with standerdization 0.1NaOH -Calculate the (volume of HCl reacted with antacid)(Vr) knowing that Volume of the end point (volume o
according to Fagan's method titrate 30m1 of the mixed halides solution (K1 +NaCI) with standard 0.1M AgNO3 using flourescein indicator, then titrate another 30m1 of the original solution (KI +NaC1) with the same titrant using eosin indicator then Calculate the concentration of each halide in the mix. In g% knowing that (V end point for flask 1(using fluorescein) =70m1 and
Again this board has been great in helping me prepare for assignments..would appreciate your help again
Consider the following reaction, and its value of K : 2 HBr(g) + Cl2(g) ⇄ 2 HCl(g) + Br2(g) K = 0.065 a. Sketch the reaction energy diagram for this reaction (reactants on the left, products on the right, and transition state in the middle). b. C
A piece of aluminum with a mass of 250. g is at an initial temperature of 5.0 °C. If 24.1 kJ is supplied to warm the Al, what is its final temperature?
the specific heat capacity of Al is 0.902J g^-1 ºC
a mix of HE, Ar, Xe has total pressure of 3.00atm. what is the pp for Xe if pp f
a mix of He,Ar,Xe has the total pressure 3.00 atm. partial pressure of He is 0.400 atm, partial pressure of Ar is 0.450 atm, what is the partial pressure for Xe?
How would you calculate the triple point if you are given, for instance, the heat of sublimation and heat of vaporization, and the temperature and pressure of a substance in solid form and in gas form?
I used a modified version of the clausius clayperon equation and used the heat of sublimation and heat of fusion but I'm not really sure if it makes sense...
If you had a dilution where you took 0.5 parts sample to 9.5 parts dilutents, what is the value of the actual dilution you performed? this is a review for us, and I forgot how to do these crazy dilution problesm,=. thx if you can help
2-How many grams of Methanol CH3OH; MM=32g/mol) must be added to a 500 mL of water to prepare a solution that is 15%(m/v) CH3OH? What is the Molarity of this solution (grams solute/mL of solution)x100; M=mols solute/L of solution)?
2HF(g) –542
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