August 21, 2014

Search: Calculate the pH of a 0.21 M CoCl3 solution. The Ka value for Co(H2O)63+ is 1.0 10-5.

Number of results: 48,319

1. calculate the volume of concentrated HNO3 (68%)that is needed to prepare stock solution 0.25M in 1000mL volumetric flask. (density HNO3 = 1.513 g/cm^3) 2. from above stock solution, determine volume needed to dilute to 500mL volumetric flask that contained 10 times dilution.
July 10, 2013 by Susan

Algebra 1
23.what is the slope of a line parallel to a line represented by the equation x=2y-3? 19.what is the solution to the following system of equation? Y=4x-8 Y=2x 16.which graph below shows the function f(x)=-3x-1? 12.what is the solution to the following system of equations? Y=2x...
January 21, 2012 by Elyon

General Chemestry
A galvanic (voltaic) cell consists of an electrode composed of chromium in a 1.0 M chromium(II) ion solution and another electrode composed of gold in a 1.0 M gold(III) ion solution, connected by a salt bridge. Calculate the standard potential for this cell at 25 C.
January 26, 2013 by Anonymous

A is a solution of HCL containing 7.30g/dm3.B is a solution ofX2CO3 containing 10.6g/dm3.assume that average volume of acid is 2.81cm3 and the volume of base is 25.00cm3.from your result and information .calculate (I)concentration of A in mol/dm3(ii)concentration of B in mol/...
May 26, 2014 by john kelechi

Prepare a theoretical titration curve for titration of 25.0 mL of 0.1037 formic acid (HCOOH; pKa = 3.75) solution (diluted to 100 mL volume with deionized water) by 0.0964 M solution of KOH. I have to determine volume of KOH needed to reach equivalence point, the pH of ...
March 5, 2012 by Clint

I posted this question on Thursday April 12 and received some help..but need more.. thanks Use the following information to identify element A and come pound B, then answer questions a and b. An empty glass container has a mass of 658.572 g. It has a mass of 659.452 g after it...
April 16, 2007 by Julia

1. the solubility of AgCl in water is 3.97x10^-6 at 0*C and 1.91X10^-4 at 100*C. calculate Ksp for AgCl at each temp. 2. using the data from #1 and the clausius- Clapeyron equation, calculate deltaH* and deltaS* for the formation of a saturated solution of AgCl. I just need ...
March 28, 2011 by anonymous

In an experiment liquid hexane, C6H14 (l) is combusted completely to produce CO2(g) and H2O (l) according to the equation: 2 C6H14 (l) + 19 O2(g) -> 12 CO2(g) + 14H2O (l) The change in H degrees for the reaction is -8.39 x 10^3 KJ. Calculate change in H degrees for C6H14 (l).
November 29, 2010 by vvvvvv

1.9 mol HCl and 3.8 mol NaOH react according to the equation HCl + NaOH −→ NaCl + H2O . Calculate the amount in moles of NaCl formed. Answer in units of mol
February 9, 2012 by Mary

In a silphuric acid (H2SO4)-Sodium Hydroxide (NaOH) acid-base titration, 17.3mL of 0.126M NaOH is needed to neutralize 25mL of H2SO4 of unknown concentration. What is the morality of the H2SO4 solution? H2SO4 (aq)+ NaOH (aq) = Na2SO4 (aq) + H2O (l)
July 1, 2014 by Dawn

A lab needs a 20 liters of a 15% acid solution. The lab only has a 10% acid solution and a 30% acid solution. How much of the 10% acid solution will they need to mix with the 30% solution to obtain 20 liters of a 15% solution?
April 2, 2013 by Anonymous

The empirical formula for Brilliant Blie dye is C37 H34 N2 O9 S3 Na2, and the formula weight is 792.86 g/mol. How would you prepare a 4.73 X 10^-6 M solution of Brilliant Blue dye? How many grams of the dye do you need to add to a 1.00 L of water to make this solution? I have ...
October 12, 2011 by Hannah

Ethanol, C2H5OH or C2H6O, is mixed with gasoline and sold as gasohol. Given the following thermo-chemical reaction, calculate the kilograms (kg) of CO2 produced when enough ethanol is combusted to provide (or give off) 369 kJ of heat: C2H5OH (l) + 3 O2 (g) --> 2 CO2 (g) +3 ...
July 12, 2011 by Robert

Given the thermochemical equation below, calculate the amount of energy released when 250. g of NaOH (molar mass = 40.0 g/mol) reacts with an excess of HCl. Report answer to the correct number of significant figures in units of kilojoules, kJ. NaOH + HCl --> NaCl + H2O ...
April 25, 2013 by sarah

Calculating DHrxn?
What is DHrxn for the following reaction, CH4(g) + 2 O2(g) ---> CO2(g) + 2 H2O(l), given DHf[CH4(g)] = -74.8 kJ; ...DHf[CO2(g)] = -393.5 kJ; ...DHf[H2O(l)] = -285.5 kJ. a. ) -604.2 kJ b. ) 869.7 kJ c. ) -997.7 kJ d. ) -889.7 kJ e. ) 997.7
June 12, 2009 by AnthoniiEllis

Calculate the H rxn for the following reaction. H f [H2S(g)] = -21 kJ/mol; H f [SO2(g)] = -297 kJ/mol; H f [H2O(l)] = -285.8 kJ/mol; 2H2S(g) + SO2(g) 3S(s) + 2H2O(l) a. 232.6 kJ b. 910 kJ c. -232.6 kJ d. -910 kJ
August 22, 2010 by Lucinda

math who me step by step
25g of a sample of ferrous sulphate was dissolved in water containing dilute h2s04 and the volume made up to one litre. 25ml of this solution required 20ml of N/10 kmn04 solution for complete oxidation. Calculate the percentage of fes047h20 in the sample the right answer 88.96...
January 1, 2014 by Fai

Alyssa is a chemist with Gemco Pharmaceutical Company. She needs to prepare 12 ounces of 9% hydrochloric acid solution. The only solution she currently has available are 4% and 12% hydrocholoric acid. How much should she use of each solution to obtain the needed solution.
March 9, 2011 by John

write a balanced equation for the combustion of benzene. All hydrocarbons, like benzene are, are the same. Add O2. C goes to CO2 and H goes to H2O. C6H6 + O2 ==> CO2 + H2O I will let you balance it. Let me know if you have a problem with it. would it be... C6H6 + 14O2 -->...
August 6, 2007 by Anonymous

i have a lab where we used VI method to calculate resistance of a LARGE resistor... circuit is as follows..(--- indicates wire) source---ammeter---resistor(voltmeter connected in parralel to resistor)---(connected back to source) the R value calculated was wrong. i need to ...
February 9, 2010 by SAM

A 0.8870g sample of a mixture of nacl and kcl is dissolved in water and the solution is then treated with an excess of agn03 to yield 1.913g of agcl. Calculate the percentage by mass of nacl in the mixture 1.913g/ 143 = 0.0133 M agcl x/58 + Y/74 (0.887g-x) = 0.0133 Who helps ...
January 19, 2014 by Carlos

Mass Transfer
Solution of methanol and ethanol are substantially ideal. (a) Compute the vapour-liquid equilibria for this system at 1 and at 5 atm abs pressure, and plot xy and txy diagrams at each pressure (b) For each pressure compute relative volatilities , and determine an average value...
April 8, 2014 by RHS

How do I find the molarity of NaCl for different dilutions? You calculate the number of moles per liter of solution.
April 8, 2007 by Colleen

Hydrogen cyanide is a weak acid with Ka = 4.9 x 10-10. Calculate the pH of a solution (to 2 decimal places) containing 2.28 g of Sr(CN)2 per 158 mL.
January 7, 2008 by Andrew

calculate the number of grams of co2 that can be absorbed by complete reaction with a solution that contains 5.00 g of sodium hydroxide
February 9, 2010 by Anonymous

Can i please get a formula to calculate the concentration of an acid when it reacts with a standard solution? ( preferably 0.1 M NaOH and viniger )
August 5, 2010 by Daniel

calculate the amount of solid NH4Cl to add to 50 mL of 1 M to form a mixture that has a pH of 9 assume no volume change in the solution
October 6, 2010 by maycee

Hi please help with this. You will mix 5 ml of each 2M HCL and 2M NaOH solutions, calculate the concentration of NaCl formed in the new solution?
October 17, 2010 by John

calculate the molarity of 70.7g C2H6O in 2.25 L of solution, can someone walk me through this and provide the right answer? please and thank you =))
December 3, 2010 by Jenni

Calculate the Ksp Ca(OH)2 25cm3 of a saturated solution required 11.45cm3 of 0.1mol/dm3 HCl for neutralization.
January 3, 2011 by Suha

Calculate the percent mass of a solution made by dissolving 25.2 of KBr into .250 liters of water.
February 22, 2011 by yoda

0.1M solution of methanoic acid is found to have a ph of 2.4 at 25 degree celcius. Calculate the dissociation constant k at this temperature.
March 26, 2011 by Olamide

Calculate the mass of silver nitrate needed to prepare a solution of concentration 0.01 moles per litre
April 4, 2011 by Anonymous

Calculate mass of silver nitrate needed to prepare a solution of concentration 0.01 moles per liter.
April 5, 2011 by Slim Shady

For a solution that is 0.280 M HC3H5O2 (propanoic acid Ka=1.3*10^-5) and 0.0894 M HI, calculate the following. Concentration of H30, OH, C3H5O2-, I-
April 14, 2011 by Joe

A 1.00 L solution saturated at 25C with lead(II) iodide contains 0.54 g of PbI2. Calculate the solubility-product constant for this salt at 25C. thanks
April 27, 2011 by Rebekah

Chemistry II
Calculate how many milliliters of 0.100 M HCl must be added to 25.0 ml of a 0.200 M solution of NH3 to prepare a buffer that has a pH of 9.50? Kb = 1.76 x 10^-5
June 29, 2011 by Terence

Calculate the molecular mass of sulphur if 35.5 g of sulphure dissolves in 1 00 g of CS2 to produce a solution that has a boiling point of 49.48 c.
November 2, 2011 by Ethio

Cert III lab skills
Explain how to calculate preparing 250.0ml of 1.25 mol/L solution of Na2CO3(aq)
November 29, 2011 by lisa

AP Chemistry
A solution is prepared by mixing 50.0 mL of 0.17 M Pb(NO3)2 with 50.0 mL of 1.6 M KCl. Calculate the concentrations of Pb2+ and Cl - at equilibrium. Ksp for PbCl2(s) is 1.6X 10-5.
December 4, 2011 by Bill

calculate the mass of silver nitrate present in 10mL of a 0.5M solution. will someone show me how to do this because i have no idea :(
December 7, 2011 by Tabatha

how do i calculate the number of moles of ammonium iron (ll) sulphate (NH4)2 Fe(SO4)2.6H2O in 1dm3 of solution?
December 30, 2011 by jevoy

Calculate the volume of .300 M NaOH needed to prepare a pH=3.50 buffer with 250ml of .075M HF solution. pKa (HF) = 3.15
February 11, 2012 by Will

Calculate the freezing point depression of an aqueous solution prepared by mixing 22.0 g C6H12O6, with 600 ml of water
February 20, 2012 by Kristen

A 1.00-L solution saturated at 25C with lead(II) iodide contains 0.54 g of PbI2. Calculate the solubility-product constant for this salt at 25C.
March 3, 2012 by DAN

Chemistry help PLEASE!!
For a solution that is 0.168 M NH3 and 0.104 M NH4Cl calculate the following.? [OH-] [NH4+] [Cl-] [H3O+] How would you do this :-/
March 12, 2012 by Anonymous

calculate the ionisation constant of the conjugate base of a solution made from 0.20M HC2H3O2 AND 0.50M C2H302.
March 31, 2012 by laze

Chemistry(Please help)
Calculate the pH of an aqueous solution of 0.15 M potassium carbonate. I know that pH = -log(H30+) but I am not sure how to start this problem.
April 14, 2012 by Hannah

Chemistry(Please help)
Calculate the concentration of HC6H6O6- in an aqueous solution of 0.0851 M ascorbic acid, H2C6H6O6 (aq). I do not know how to start this
April 15, 2012 by Hannah

college chemistry
Followed by the total volume. Calculate the molarity of this solution: 0.521 mol NaCl;125 mL
April 16, 2012 by michelle

calculate the volume in ml of 0.250 M silver nitrate solution required to react completely with a 5.00 g piece of copper
April 19, 2012 by No

calculate the volume in ml of 0.250 M silver nitrate solution required to react completely with a 5.00 g piece of copper
April 19, 2012 by No

how to Calculate the molarity of a solution if sulphuric acid contains 13%H2SO4 by mass and density is 1.02 gm per cm3.
May 4, 2012 by hari

how to Calculate the molarity of a solution if sulphuric acid contains 13%H2SO4 by mass and density is 1.02 gm per cm3.
May 4, 2012 by hari

Pb(NO3)2(aq) + NaSO4(aq) → PbSO4(s)+ 2NaNO3(aq) Identify the ions that are present in each solution, and calculate their concentrations.
May 16, 2012 by Sam

Chem 2
Using the reaction HB<=> H+ + B- and the Ka for that expression, calculate the Ka given the initial concentration of weak acid to be 0.150 M and the pH of the solution to be 2.79.
July 27, 2012 by Myssey

A solution is prepared by mixing 50.7 mL of 0.28 M Pb(NO3)2 with 70.8 mL of 1.0 M KCl. Calculate the concentrations of Pb2+ and Cl - at equilibrium. Ksp for PbCl2(s) is 1.6 10-5.
February 21, 2013 by jeff

Calculate the percent ionization of 0.140 M lactic acid in a solution containing 8.510−3 M sodium lactate.
April 27, 2013 by John

Chemistry 12
Calculate the volume of 12 M Na2SO3 which needs to be added to 500.0 mL of water in order to produce a solution in which [Na+]= 0.200 M.
October 8, 2013 by Riann

A 200.0mL solution with 3.1 x 10^-3 mol of MA will begin to precipitate at 19.4 C. Calculate each of the following at this temperature. a) Ksp b)change in G
April 13, 2014 by KAMILAH

50.0cm^3 of 2.0 mol dm^-3 aluminium sulphate,Al2(SO4)3 solution Calculate the number of moles of ions.
May 7, 2014 by mandy

Chemistry 12
calculate the Ph of a solution composed of 0.75 grams of KOH dissolved in 500ml of water. assume total ionization.
June 27, 2014 by jeremy

NaOH(s)+ H2SO4(aq)=Na2SO4(aq) + H2O(l) Consider the unbalanced equation above.A 0.900 g sample of impure NaOH was dissolved in water and required 37.0 mL of 0.145 M H2SO4 solution to react with the NaOH in the sample. What was the mass percent of NaOH in the sample?
February 26, 2010 by Tiffany

For each of the following unbalanced equations, suppose that exactly 15.0g of each reactant is taken. Determine which reactant is limiting, and calculate what mass of each product is expected. assume the limiting reactant is completely consumed. a)Al+HCL->AlCl3+H2 b)NaOH+...
February 16, 2009 by Megan

an auditor wishes to test the assumption that the mean value of all accounts receivable in a given firm is $260.00 she will reject this claim only if it is clearly contradicted by the sample mean. the sample standard deviation of 36 accounts is $43, the sample mean is $250, ...
April 29, 2012 by b

a mixture of methane and ethane is stored in a container at 294 mmHg. The gases are burned in air to form co2 and h2o. if the pressure of co2 is 357 mmhg measured at the same temperature and volume as the original mixture, calculate the mole fraction of the gases.
December 4, 2010 by maggie

When 0.949 g of CaO is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 389C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. what is molar heat of reaction, Hrxn, for the reaction of CaO...
February 15, 2010 by blasting

March 8, 2007 by Desmond

A mixture of CuSO4 and CuSO45 H2O has a mass of 1.235 g. After heating to drive off all the water, the mass is only 0.830 g. What is the mass percent of CuSO45 H2O in the mixture?
September 22, 2010 by Noelle

a solution is prepared using .015 L of 1.0 M HCl and .020 L of .50 M HNO3. the final volume of the solution is 1.25 L. Answer th following questions. a)what are the [H3O+] and [OH-] in the final solution? b)What is the pH of the final solution?
May 4, 2010 by Alexa

Consider the following buffer equilibrium: HF (high concentration) + H2O <--> H3O+ (low concentration) + F- ( high concentration) Using Le Chatelier's Principle, explain what happens to the pH of the buffer solution when a small amount of NaOH is added. Wouldn't OH- ...
June 3, 2010 by sh

A galvanic (voltaic) cell consists of an electrode composed of magnesium in a 1.0 M magnesium ion solution and another electrode composed of copper in a 1.0 M copper(I) ion solution, connected by a salt bridge. Calculate the standard potential for this cell at 25 dC.
April 1, 2013 by Anon

14.what value of n will result in a mean if 31 15.what value of n will result in a median of 23 15.what value of a will result in a range of 84 14,46,19,10,39,22,24,77,n Refresh your memory about the defnition of median, mode and range of a set of numbers. Then pick a value of...
March 4, 2007 by alice

3. When a mixture of 10.0 grams of acetylene (C2H2) and 10.0 grams of oxygen (O2) is ignited, the resulting combustion reaction produces CO2 and H2O. A) Write a balanced equation for this reaction. B) What is the limiting reactant? C) How many grams of C2, H2, O2, CO2, and H2O...
May 14, 2013 by tra

Given that g(x)= 2x+1/5 and f(x)=x+4 Calculate the value of g(-2) 2(-2)+1/5= -3/5 Is this right?? How do i write an expression for gf(x) in the simpliest form?? And how do i find inverse functions such as g`1(x)?
June 30, 2009 by Maxine

How do I calculate a present value? 7,000 in 5 years at a quarterly discount rate of 6% I have looked at the material, but I am confused. Thank you
April 22, 2011 by Nancy

What is the value of the rate constant at 17 degrees celsius? The Ea = 122 kJ/mol I know I have to use ln k = ln A - Ea/RT.. but I don't know how to calculate it without known ln A and how do you find ln A Thank you for your help!
February 6, 2012 by Vicky

Physical Chemistry
Calculate the value of the change in enthalpy(H) when the temperature of 1 mole of a monatomic gas is increased from 25C to 300C.
March 4, 2012 by J

The value of H for the reaction below is -482 kJ. Calculate the heat (kJ) released to the surroundings when 12.0 g of CO(g) reacts completely. 2CO(g) + O2(g) 2CO2(g)
June 6, 2012 by Harlem

Calculate the future value of $5000 given that it will be held in the bank for 6 years and arn an annual interest rate of 7%.
May 8, 2013 by Jeff

Calculate the present value for $1400 needed in 4 years, invested at 4.2% per year compounded semi-anually
June 16, 2013 by Courtnie

Calculate the present value for $1400 needed in 4 years, invested at 4.2% per year compounded semi-anually
June 16, 2013 by Courtnie

calculate the total surface area of a solid cone of slant height 10cm. use the value 3.14 for radius
May 2, 2014 by Edward

For the graphed function f(x) = (4)^(x - 1)+ 2, calculate the average rate of change from x = 2 to x = 4 -68 -30 68 30 Which logarithmic graph can be used to approximate the value of y in the equation 4y = 8?
May 13, 2014 by Stokedtobehere

Use standard enthalpies of formation to calculate the value of delata H degree for the rxn:NH3(g) + 3F2(g) = NF3(g) + HF(g)
July 26, 2014 by Padlock

A house had an original value of $80,000. After 2 years, the new value became $120,000. Find the ration, as a fraction in simplest form, of the increase in value to the original value.
September 14, 2009 by Sandra Aged College Student

The following reaction was carried out in a 2.00 reaction vessel at 1100 : C+H2O -> C)+H2 If during the course of the reaction, the vessel is found to contain 7.00mol of C, 13.3mol of H2o, 3.80mol of CO, and 7.20mol of H2, what is the reaction quotient ? Enter the reaction ...
April 28, 2013 by JAclyn clark

Aqueous solutions of Zn+2 and Pb+2 both .0010M. Both form insoluble sulfides. Appx. what pH will allow maximum precipitation of one ion and leave the other in solution? Do I just use Ksp and the equations? If so what do I do next? See the selective solubility notes and example...
May 7, 2007 by Anonymous

Simpson's rule
Is the simpson's rule always more accurate than the midpoint rule and trapezoidal rule? Not always; it is possible that the midpoint and/or trapezoidal rule determine exact values. 1. Some functions values for a function f are given below. x 0 0.5 1.0 f(x) 3 4 11 What is the ...
October 24, 2006 by 413

Math help!
1.(g + 4) - 3g = 1 + g 1 4 No solution Identity 2. 5y + 2 = 1/2(10y + 4) 5 10 No solution Identity 3. 0.5b + 4 = 2(b + 2) 0 0.5 No solution Identity 4. -3x + 5 = -3x + 10 5/6 -5/6 No solution Identity My answers: 1. 1 2. Identity 3. 0 ??? Not sure 4. No solution I really need ...
October 1, 2013 by Charlotte

Inorganic chemistry
MnO4^-(aq) + H20(l) ==> MnO2 + OH^- net charg is -1 +7 (-8) ==> 4(-4) Manganese is reduced MnO4^- +3e- ==> MnO2 H2) is the oxidizing agent in a basic solution Mno4^- + H2O(l) --> MnO2(s) + OH^- Add on OH^- to both sides of the equation for every H+ ion present ...
April 14, 2009 by Steve

I definately do not understand this problem. If y varies directly with x, and y = 600 when x = 1000, find the constant of variation K. If y is directonally (proportional) to x, then for every value of x there is a value for y multiplied by a constant value. So if was that we ...
March 31, 2007 by jacky

A student determined the chloride content of a commercial salt by using the Mohr method. A 0.5324 -g sample of the salt was dissolved in distilled water and diluted to a final volume of 250. mL. A 25.-mL aliquot of the analyte solution was then titrated against a standard 0....
April 4, 2011 by tara

The value of the equilibrium constant (Kp) as represented by the first chemical equation is 1.02 x 102 at 727 C. Calculate the value of the equilibrium constant (Kp) for the second equation at the same temperature. Express answer in scientific notation. 2F(g) = F2(g) F2(g) = ...
April 13, 2010 by Amphee

Wheel Industries is considering a three year expansion project. The project requires an initial investment of $1.5 million. The project will use straight line depreciation method. The project has no salvage value. It is estimated that the project will generate additional ...
April 22, 2010 by Shelly

I was just wanting to make sure I did these right. How many grams of solute are in each of the following solutions? a.) 2.5 L of 3.0 M Al(NO3)3 solution. for this one I get 1600 g of Al(NO3)3 b.) 75 ml of 0.5 M C6H12O6 solution. and for this one I get 6.8g of C6 H12 O6 How ...
November 29, 2010 by Carrie

A solution contains 0.01M ethyl acetate, 0.10M acetic acid and 0.10M ethanol. For the same equilibriujm constant of 2.00, calculate the equilibrium concentrations of ethyl acetate, ethanol, and acetic acid in the solution.
July 24, 2012 by Eric

Freezing point of pure water = -2, Freezing point of Unknown solution = -1 Mass of unknown in 50g of water = 1.9964g. Calculate the delta T for the solution of the unknown solid and determine the molecular weight of the unknown solid.
February 2, 2013 by Anna

use thermochemical equations shown below to determine enthalpy for the reaction: H2CO3-->H2O+CO2 1) H2CO3 --> H2CO + O2 H; 224 KJ 2)H2CO + O2 --> H2O + CO2 H; -100KJ I know this problem is one that you have to rewrite the equations to get the equation in the original ...
November 20, 2009 by Brittany

use thermochemical equations shown below to determine enthalpy for the reaction: H2CO3-->H2O+CO2 1) H2CO3 --> H2CO + O2 H; 224 KJ 2)H2CO + O2 --> H2O + CO2 H; -100KJ I know this problem is one that you have to rewrite the equations to get the equation in the original ...
November 20, 2009 by Brittany

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