Number of results: 68,281
A solution of ferrous sulfate (FeSO4) is titrated with a solution of potassium permanganate in sulfuric acid. The balanced half reactions are as follows: 10FeSO4 + 5 H2SO4 --> 5 Fe2(SO4)3 + 10 H ^+ +10e^- and 2 KMnO4 + # H2SO4 +10e^- --> 2 MnO4 + K2SO4 + 8 H2O. The gram...
January 5, 2010 by amy
Could someone help me with these problems; A)If 5.97mL of a solution of NaCl contains 2.54g of sodium ion, what is the molarity of the sodium chloride solution? -I know M=#moles solute/L but when I do this I get 7.28*10^-3 which is wrong, the answer should be 1.85*10^-2 B) ...
January 28, 2011 by Adam
Given a diprotic acid, H2A, with two ionization constants of Ka1 = 3.9× 10–2 and Ka2 = 5.9× 10–8. Calculate the pH and molar concentrations of each protonated form for a: (a)0.135 M solution of H2A pH= [H2A]= [HA]= [A2-]= (b)0.135 M solution of NaHA pH= [H2A]= [HA]= [A2-]= (c)...
July 21, 2012 by Jo
Calculate ΔG at 25°C for the precipitation of lead(II) chloride from mixing 100. mL of 0.025 M lead(II) nitrate solution with 100. mL of 0.15 M sodium chloride solution. The ΔG° for the reaction at 25°C = −27.36 kJ/mol. (Hint: write out reaction equation – also...
October 2, 2012 by Ashley
If 20.00mL of a solution that contains oxalate ion requires 10.00mL of 0.020M MnO4- solution in a titration, what was the molarity of the oxalate solution? 5C2O42- + 2MnO4- + 12H+ --> 2Mn2+ + 10CO2 + 8 H2O
March 23, 2010 by Megan
The solubility of CaSO4 is 0.209 g/100 mL of water at 30 degrees celsius. if 0.500 g CaSO4 is stirred overnight at 30 Degrees Celsius with 100.0 mL of water, a. How many grams of CaSO4 remain undissolved? b. Calculate the molarity of CaSO44 in solution
October 25, 2012 by Anne
A .682 g sample of an unknown weak monoprotic acid, HA, was dissolved in sufficient water to make 50mL of solution and was titrated with a .135 M NaOH solution. After the addition of 10.6mL of base, a pH of 5.65 was recorded. The equivalence point was reached after the ...
May 9, 2007 by Sara
I don't get two questions out of my homework and I know the answers to them but just not how the answers were gotten. PLEASE HELP!! 1) A handbook gives the aqueous solubility of carbon monoxide at 0 C and 1 atm CO pressure to be 0.0354 mg CO per mL of solution. What would be ...
February 13, 2012 by Taylor
Assuming that sea water is a 3.5 wt% solution of NaCl in water, calculate its osmotic pressure at 20 deg C. The density of a 3.5% naCl solution at 20 deg C is 1.023 g/mL. How do I go about solving this?
February 28, 2008 by Sarah
1.Write a mathematical equation that can be used to calculate the concentration of the HCl solution after the standardization procedure (Titration #1). 2. Using LeChatelier’s principle, predict whether [OH-] in the calcium hydroxide/0.050 M NaOH solution is expected to be ...
April 16, 2012 by Cassie
when 5.0g of KOH is added to 100mL, of water, the temperature of the solution increases by 3 degrees celsius. Assume the density of the solution to be 1g/mL and specific heat capacity of the solution to be 4.184 J/g K. a. calculate the amount of heat absorbed by the solution. ...
March 27, 2012 by danielle
I have these two questions on my section review that I don't know how to answer. Can someone help me? Please and thank you. 3. Describe in your own words how to prepare 100 mL of a .85 M solution of sodium chloride. 4. If you dissolve 2.00 mol KI in 1.00 L of water, will you ...
April 29, 2010 by Ana
Organic Chemistry - Extraction
You have 100 mL of a solution of benzoic acid in water; the amount of benzoic acid in the solution is estimated to be about 0.30 g. The distribution coefficient of benzoic acid in diethyl ether and water is approximately 10. Calculate the amount of acid that would be left in ...
October 3, 2010 by Camille
A student mixed 15.0 mL of a solution of 0.0200 M ferric chloride FeCl3, with 25.0 mL of water. Calculate the moles of iron ion, Fe +3 in the resulting solution. (I think this is a Dilution problem, but I wasn't really sure how to start it out. Any help would be greatly ...
January 23, 2012 by S
Assume you dissolve 0.235 g of the weak acid benzoic acid, C6H5CO2H, in enough water to make 4.00*10^2 mL of solution and then titrate the solution with 0.138 M NaOH. C6H5CO2H(aq) + OH-(aq) C6H5CO2-(aq) + H2O(l) Find concentration of Na+ at equivalence point.
April 21, 2013 by john
A 15.00 g sample of an ionic compound NaA, where A- is the anion of a weak acid, was dissolved in enough water to make 100.0 mL of solution and was then titrated with 0.100 M HCl. After 700.0 mL of HCl was added, the pH was 5.00. The experimenter found that 1.40 L of 0.100 M ...
March 15, 2012 by Ashley
A buret (initial and final buret reading were 2.20 mL and 11.86 mL) was used to deliver a sample of 2.1E-5 M stock dye into a 25.0 mL volumetric flask. The dye was then diluted with water to exactly 25.0 mL. Calculate the molarity of the resulting solution.
October 26, 2010 by Mallory
Lead pipes were once used to transport drinking water and are still found in some older homes and city water systems. Suppose the lead concentration and pH of the water determined by lead (II) hydroxide (Ksp = 2.8x10^-16) dissolving to produce a saturated solution. What would ...
March 25, 2011 by abbey
NH4NO3(s) NH4+(aq) + NO3−(aq) In order to measure the enthalpy change for this reaction above, 1.07 g of NH4NO3 is dissolved in enough water to make 25.0 mL of solution. The initial temperature is 25.8°C and the final temperature (after the solid dissolves) is 22.4°C. ...
November 16, 2012 by DeeDee
If a student used 11.54mL of their NaOH solution to neutralize 10.00mL of a 0.445M KHP solution, then what is the concentration of the student's NaOH solution (in Molarity)?
October 4, 2010 by Ari
A solution of ferrous sulfate (FeSO4) is titrated with a solution of potassium permanganate in sulfuric acid. The balanced half reactions are as follows: 10FeSO4 + 5 H2SO4 --> 5 Fe2(SO4)3 + 10 H ^+ +10e^- and 2 KMnO4 + # H2SO4 +10e^- --> 2 MnO4 + K2SO4 + 8 H2O. The gram-...
January 4, 2010 by Amy
A commercial sample of concentrated aqueous nitric acid (HNO3) is 18.2% nitric acid base mass and has a density of 1.12 g/mL. (a) What is the molarity (M) of the HNO3 solution? (b) What is the molality (m) of the HNO3 solution? -------- I know that.... (a) molarity = moles of ...
January 21, 2009 by Sarah
Instant cold packs, often used to ice athletic injuries on the field, contain ammonium nitrate and water separated by a thin plastic divider. When the divider is broken, the ammonium nitrate dissolves according to the following endothermic reaction: In order to measure the ...
November 1, 2011 by Lindsey
calculate the volume(ml) of a 0.215M KOH solution that will completely neutralize each of the following? a) 2.50ml of a 0.825M H2SO4 solution b) 18.5ml of a 0.560 M HNO3 solution c) 5.00mL of a 3.18 M H2SO4 solution
April 28, 2011 by Connie
A solution contains 0.0653g of compound in 8.31g of ethanol. The molarity of the solution is 0.0368m. Calculate the molecular weight of the compound For Further Reading Chemisty - drbob222, Thursday, February 7, 2008 at 9:40pm The molarity of the solution can't be 0.0368 m. It...
February 9, 2008 by Lauren
A calorimeter contains 21.0 mL of water at 12.0 degress Celsius. When 2.40g of X (a substance with a molar mass of 50.0 g/mol ) is added, it dissolves via the reaction X(s)+H2O(l) --> X (aq) and the temperature of the solution increases to 29.5 degress celsius. Calculate ...
September 23, 2008 by Sarah
Three solutions are mixed together to form a single solution. One contains 0.2 mol Pb(CH3COO)2, the second contains 0.1 mol Na2S, and the third contains 0.1 mol CaCl2. Write the net ionic equations for the precipitation reaction or reactions that occur.
April 29, 2011 by Michelle
What mass of CsBr must be added to .500L of water to produce .4molality solution? What are mole fraction and mass percent? Here is my work and below I will post a question about it: 1 mol CsBr = 212.81g density of water = 1g/mL d=mv 1=x/500 x=500g of water --> solvent ....
February 18, 2010 by Chem
A 0.753 m solution of the solute CH3CN dissolved in the solvent C6H6 is available. Calculate the mass ( g ) of the solution that must be taken to obtain 3.274 mol of CH3CN. Additional info: Molar Mass (g/mol) CH3CN 41.05 C6H6 78.11 Density ( kg/L ) CH3CN 0.7857 C6H6 0.8786 ...
May 8, 2010 by Kyo
Concentrated sulfuric acid is 18.4 molar and has a density of 1.84 grams per milliliter. After dilution with water to 5.20 molar the solution has a density of 1.38 grams per milliliter. This concentration of H2SO4 is often used in lead storage batteries(like a car battery). 1...
January 13, 2011 by Kevin
In a study designed to prepare new gasoline resistant coatings, a polymer chemist dissolves 6.053g of poly in enough water to make 100.0 mL of solution. At 25C, the osmotic pressure of this solution is 0.272 atm. What is the molar mass of the polymer sample?
March 26, 2010 by Mike
What is the concentration in mol/L of a CuSO4 solution containg 1.0 mole of CuSO4 in 250 mL of Solution? I would like to know how to calculate the answer and be giving the correct answer please.
November 19, 2012 by Hannah
25.00 mL of an acetic acid solution requires 23.86mL of a 0.1550M potassium hydroxide solution to reach the end point. What is the molarity of the acetic acid solution? (Hint: write the chemical reaction, and remember stoichiometry)
April 6, 2010 by shelley
A.Determine the pH of the solution. a solution that is 1.17% HCl by mass (Assume a density of 1.01 g/mL for the solution.) B. Amphetamine (C9H13N) is a weak base with a pKb of 4.2. Calculate the pH of a solution containing an amphetamine concentration of 279 mg/L.
July 3, 2012 by Anonymous
college chem 2
Calculate the deltaS univ for the dissolving of NaCl at room temp. S' NaCl(s)=72.11 J/k*mol; S' NaCl(aq)=115.5 J/k*mol;deltaH' NaCl(s)=-411.12 kJ/mol; deltaH' NaCl(aq)=-407.27 kJ/mol.
March 24, 2014 by shel
I am doing a titration lab and need help with a problem. (i used .100M H2SO4)(I used 10.0 ml of Ba(OH)2 solution and added 50.0 ml of distilled water making 60.0 ml total.) 1. Use the titration results to calculate the moles of H2SO4 that were used to reach the equivalence ...
October 12, 2013 by Charles
When 20.8 g of calcium chloride, CaCl2, was dissolved in water in a calorimeter, the temperature rose from 25.0°C to 37.1°C. If the heat capacity of the solution and the calorimeter is 1258 J/°C, what is the enthalpy change when 1 mol of calcium chloride dissolves in water? ...
October 18, 2008 by Glenna
Indicate the concentration of each ion present in the solution formed by mixing the following. (Assume that the volumes are additive.) (a) 50 mL of 0.100 M HCl and 10.0 mL of 0.510 M HCl (b) 15.0 mL of 0.309 M Na2SO4 and 38.6 mL of 0.200 M KCl (c) 3.50 g of NaCl in 40.2 mL of ...
September 21, 2011 by Anonymous
Can u please check these questions..thanks! Redox Stoichiometry 1.A 2.45g zinc metal strip is placed into an 2.3 x 10-1 mol/L solution of tin (II) bromide. If all the zinc and tin (II) bromide react, what was the volume of the solution. My answer: 8.62L is the volume of the ...
July 12, 2006 by Dave
A dilute electrolyte solution is prepared by dissoving iron (III) chloride in water. It is found to have a freezing point of -2.10 degrees C. Calculate the molality of the solution.
October 18, 2010 by Gracyn
how would you do this question when i did it i did -log(1.0) but that is just 0 so what it the procedure to do this question Calculate the pH of a 1.0 mol/L aqueous solution of sodium benzoate. Note: Only the benzoate ion affects the pH of the solution.
June 7, 2014 by Annie
1. Calculate the volume of carbon dioxide at 273 K and 1.01 * 10^5 Pa which would be produced when 1.25g of calcium carbonate reacts completely with HCL. and 2. When 41.18 cm^3 of a solution of silver ions with concentration of .2040 mol dm^-3 is added to a solution of XO4 -3 ...
May 19, 2008 by ANn
what is the molarity of a solution of KNO3(molecular mass=101) that contains 404 grams of KNO3 in 2.00 liters of solution? A. 1.00M b. 2.00M c. 0.500M d. 4.00M The definition of molarity is #mols/Liter of solution. Convert 404 g KNO3 to mols (mols = g/molar mass) and plug into...
March 26, 2007 by Kat
What is the freezing point (°C) of a solution prepared by dissolving 11.3 g of Ca(NO3)2 in 115 g of water? The molal freezing point depression constant for water is 1.86°C/m. (Note that when Ca(NO3)2 dissolves in water Ca2+ and NO32- ions are produced).
May 25, 2012 by Henry
The concentration (M) of HCl in a solution prepared by dissolving 5.5 g of HCl in 200 g of C2H6O is ?????? M. The density of the solution is 0.79 g/mL. A) 21 B) 0.93 C) 6.0 × 10-4 D) 1.72 E) 0.58
September 26, 2010 by benju
Hi I'm stuck on these questions can you please help me A soil sample contains 0.2234 g of Fe3+ per 100g. Fe3+ is precipitated when the soil becomes alkaline as shown in the equation below. Fe3+ + 3OH- + (x-1)H2O „_ FeOOH.xH2O(s) This soil is sprayed with 40.0 wt% urea solution...
March 26, 2010 by Sarah
Hi I just need help with question (ii) and (iii), i know how to work out (i) A solution is prepared by dissolving 0.2222 (±0.0002) g of KIO3 in 50.00 (±0.05) mL (i) Calculate the molar mass of KIO3 with its associated uncertainty to the correct number of significant figures. (...
March 26, 2010 by Jenny
A 25-mL sample of 0.160M solution of NaOH is titrated with 17 mL of an unknown solution of H2SO4. What is the molarity of the sulfuric acid solution? A. 0.004M H2SO4 B. 0.235M H2SO4 C. 0.117M H2SO4 D. 0.002M H2SO4
February 18, 2014 by Elizabeth
How many moles of potassium iodide, KI, are required to precipitate all of the lead(II) ion from 25.0 mL of a 1.6 M Pb(NO3)2 solution? A. 0.020 mol B. 0.040 mol C. 0.080 mol D. 0.64 mol E. 64 mol
April 28, 2013 by victoria
An aqueous solution contains 0.216 M ascorbic acid (H2C6H6O6) and 0.131 M hydrochloric acid. Calculate the ascorbate (C6H6O62-) ion concentration in this solution. [C6H6O62-] =______________ mol/L.
April 21, 2012 by Ana
A 2.00 g sample of a particular compound was dissolved in 15.0 g of carbon tetrachloride. The boiling point of this solution was determined to be 77.85ºC. For pure CCl4, TB = 76.50ºC and KB = 5.03°C·kg/mol Calculate the boiling point elevation, ΔTB, for this solution.
May 4, 2014 by sarah