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December 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: 50,994

trig
If x and y are complementary angles and 5 tan x-12=0,calculate by using a diagram the value of 2sin(squared)x+cos y.
May 3, 2012 by Francis

chemisry
Calculate how long it will take for the conctration of SO2Cl2 in the reactor in part (a) to fall to 1/4 of its initial value.
May 30, 2013 by Anonymous

Financial Management
Calculate the present value of $25,000 to be received in 5 years, assuming an opportunity cost of 10%.
October 26, 2014 by kai

college chemistry
A zinc-copper battery is constructed as follows: Zn | Zn+2(0.10 M) || Cu+2 (2.50 M)| Cu The mass of each electrode is 200.0 g. Each half cell contains 1.00 liter of solution. a) Calculate the cell potential when this battery is first connected. b) Calculate the cell potential ...
April 28, 2010 by Stephanie

Chemistry (Equilibrium)
Consider the following equilibrium system at 900C: H20(g) + CO(g) <==> H2(g) + CO2(g) Initially 5.0 moles of H2O and 4.0 moles of CO were reacted. At equilibrium, it is found that 2.0 moles of H2 are present. How many moles of H2O remain in the mixture? Would be greatly...
November 12, 2014 by Jessica

chemistry
A sulfuric acid solution at 25 C has a density of 1.27 g/mL. A 20.0-mL sample of this acid is measured out at 25 C, introduced into a 50-mL flask, and allowed to cool to 21 C. The mass of the flask plus solution is then measured at 21 C. Use the stated data, as necessary, ...
May 25, 2009 by Zandria

chemistry
OKOK I know that I have posted this question but I just don't understand the last part. 50.0 ml of a 0.0500 M solution of lead (II) nitrate is mixed with 40.0 ml of a 0.200 M solution of sodium iodate at 25C. Calculate the Pb2+ and IO3- concentrations when the mixture comes ...
May 16, 2007 by mel

Chemistry
I can't figure out how to set up this problem...You have a large amount of 8.00 M stock solution. You need 1.80L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution?
October 5, 2011 by Nicole

Algebra
100mL of a solution contains 30 mL of acid; this is called a 30% acid solution because part 30 ---- = ---- = 0.30. whole 100 How many milliliters of acid x would need to be added to the solution to turn it into a 50% solution ? (HInt: Adding acid increases both the volume of ...
October 23, 2013 by Stacey

algebra
A chemist has a solution that is 20% HIC and a solution that is 50% HCI. How much of each solution should be mixed to attain 300ml of a solution that is 30% HCI?
February 21, 2012 by Susannah

chemistry
The balanced equation is shown below. 2 HCl(aq) +CaCO3(s)=CaCl2(aq) +H2O(l) +CO2(g) 2.00 dm3 of a 3.00 M hydrochloric acid solution is added to the kettle (this is an excess). During the reaction 1.20 dm3 of CO2 is produced (assume 250C and 1 atmosphere) How many moles of CO2 ...
October 27, 2014 by Abaoaqu

chemisrty
Q4) Suppose you prepare 950 mL of a solution by dissolving 100 grams of NaCl in 900 mL of water. Assuming the density of pure water to be 1 g/mL, answer the following questions with regards to this solution: a) What is the mass percent of water in this solution? b) What is ...
January 16, 2012 by lyan

Chemistry
Calculate the enthalpy change for: C2H4(g) + H2 --> C2H6(g) delta Hrxn: H2(g) + 1/2O2 --> H2O (l) C2H4(g) + 3O2 --> 2H20(l) + 2CO2(g) C2H6(g) + 7/2O2(g) --> 3H20(l) + 2CO2(g) I know I have to flip the third reaction but I dont know what to do next
October 29, 2014 by Jessica

chemistry help asap
Please check these thanks. 1. In a titration, 33.21 mL 0.3020M rubidium hydroxide solution is required to exactly neutralize 20.00 mL hydrofluroic acid solution. What is the molarity of the hydrofluroic acid solution? Answer: 0.502HF 2. A 35.00 mL-sample of NaOH solution is ...
February 6, 2012 by missy

probability
Let X be a continuous random variable. We know that it takes values between 0 and 3, but we do not know its distribution or its mean and variance. We are interested in estimating the mean of X, which we denote by h. We will use 1.5 as a conservative value (upper bound) for the...
April 22, 2014 by juanpro

math
how do you write an open statement involving an absolute value inequality when all you are given is the graph of the solution?
September 20, 2007 by ed

math
Note: in this equation the absolute value marks are symbolized by parenthesis. 2 is less than (4-x). Why would this have no solution? Thank you!!!
October 1, 2008 by Coralia

Math
Help-I just started Algebra II and I'm lost. What is the solution of 10 = absolute value of 7-3x. Please show steps so I can understand
September 7, 2010 by Joel

Math-Algebra-Please check
What is the solution of 3 times the absolute value of x + 5 <= 6 I think the answer is x <= - 3 and x >= -7 If I'm not right, could you tell me why?
October 6, 2010 by Tanya

chemistry
I am doing a boiling point problem and dont know the value of i for the equation delta T = i(kb)(m) solution contains 45.0g caffeine in 25.0 g benzene.
December 15, 2010 by Tara

precalculus
solve the inequality algebraically. write the solution in interval notation. the absolute value of x-2/3 is less than or equal to 4
November 25, 2011 by jase

6th grade math
Determine whether each value of x is a solution of the inequality 4x-5<3 a. x=0 b. x=2 c. x=-2 d. x=4 Help please *show the work and answer!!
May 27, 2014 by mathhh HELP!! Help!!! PlEASE!!!!

Algebra I
Fill in the compound inequality 4(x-6) 2(x-10) and 5(x + 2) >/ 2(x +8) with less than, greater than, at least, or at most so that the solution is only one value
October 7, 2014 by Tonya

physics
for a damped harmonic oscillation , the equation of motion is md^2x/dt^2+(gamma)dx/dt+kx=o with m=0.025kg,(gamma)=0.07kg/s and k=85N/m. *calculate the period of motion *number of oscillation in which its amplitude will become half of its initial value *the number of ...
February 13, 2012 by ashley

Chemistry
In the reaction: MnO2 + 4 HCl ---> MnCl2 + Cl2 + 2 H2O Calculate: The volume of Cl2 produced from the reaction of 10 grams of HCl with excess MnO2?
December 13, 2010 by Darryl

Chemistry
when pure sodium hydroxide is dissolved in water , heat is evolved in a laboratory experiment measure a molar heat of solution of sodium hydroxide the following procedure was followed. to a calorimeter containing 300g of water at 20.0 C and 10.65g of NaOH also at 20.0 C was ...
March 23, 2007 by jim

Chemistry
I am so confused with my chemistry lab right now. We were given the following equations to work with: [Equation 1] 2 I^- + H2O2 + 2 H^+ ----> I2 + 2 H2O [Equation 9] 2S2O3^2- + I2 ----> 2I^- +S4O6^2- And During the Experiment we used the following for each reaction: T1...
September 20, 2014 by Bev

math, help
For the following set, which number has the largest absolute value? 4,-1,12,-20,19,0 Possible Answer of choice: A)0 B)19 C)-20 D)-1 wouldn't it be postive 20 but its not within the choices. What is the absolute value of -20? Absolute value is the distance to 0 on a number line...
February 13, 2007 by jasmine20

P Chem
5. The Li atom has three electrons. Measured values of the first and second ionization potentials are 5.3917 eV and 75.6400 eV, respectively. (i) Calculate the exactly correct value of the third ionization potential. Hint: What kind of species is Li+2? Give the result in ...
November 29, 2012 by Rebecca

Chemistry
How can i explain the key features of the periodic table relate to the conclusions after a titration experiment The experiment was the preperation of a standard solution of sodium carbonate and titration for the equation between hydrchloric acid and sodium carbonate Objective...
October 11, 2010 by Paul

Chemistry
A 0.60 L portion of a 1.2 M AgNO3 solution is mixed with a 0.3 L potion of a 1.2 M Na2CrO4 solution in an constant pressure calorimeter. Upon mixing, the solid Ag2CrO4 is formed and the heart released is 48.2 kJ. The specific heat of the solution is 4.18 J/C*g and the final ...
June 9, 2010 by Kyo

chemistry
Help with Beer's Law lab experiment question! So we were told to calculate the concentration of 5 standard solutions but I don't know how to do that exactly. The Concentration of the solution in flask B was .0024 M and our lambda max (max absorption) was at 515 nm. I know the ...
September 6, 2010 by Anonymous

Chemistry
The equilibrium constant for the reaction of the weak base aniline is Kb = 4.3e-10. C6H5NH2 (aq) + H2O (l) --> C6H5NH3+ (aq) + OH- (aq). Calculate ΔG at 298 K when [C6H5NH2] = 0.250 M, [C6H5NH3+] = 1.0E-5 M, [OH-] = 0.000480 M i used the equations dG=dG^o - RTlnQ and ...
March 25, 2014 by Brianna

algebra
Joseph always throws change into a can and takes it out every two weeks. This time it is all nickels and dimes. There are six times as many dimes as nickels, and the value of the dimes is $4.95 more than the value of the nickels. How many nickels and dimes does Joseph have. (...
April 22, 2012 by aj

maths -urgent
There is a manufacturing company who sold furniture's at the rate of Rs 31,300 per unit cost which is inclusive of 5% Value added tax. calculate the basic cost (exclusive of Value added tax) for 250 furniture's sold by the company.
April 18, 2013 by anoynomous

Chemistry
chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the student...
January 19, 2012 by Deborah

Chemistry
A chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the ...
January 19, 2012 by Deborah

Chemistry
A chemistry student weighs out 0.123 grams of chloroacetic acid (HCH2ClCO2) into a 250. milliliter volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1200 moles/liter NaOH solution. Calculate the volume of NaOH solution the ...
January 19, 2012 by Deborah

chemistry
A solution contains naphthalene(C10H8) dissolved in hexane (C6H14) at a concentration of 14.52 % naphthalene by mass.Calculate the vapor pressure at 25 degrees C of hexane above the solution. The vapor pressure of pure hexane at 25 degrees C is 151 .
August 5, 2010 by jay

Chemistry
Calculate the solid needed to make a 250ml solution that is 0.34M in sodium cation, using sodium sulfate decahydrate. I came up with 13.685g. but how do I make that into 250ml of a solution that is0.34M in sodium cation?
October 27, 2011 by Denise

oxidation
In the reaction of hydrogen peroxide with iron (II) ion in acidic solution to form iron (III) ion and water, the oxidizing agent is... ? Fe(II) ==> Fe(III) H2O2 ==> H2O. Fe goes from +2 to +3, that is a loss of electrons, so it is oxidized (by definition, oxidation is ...
April 19, 2007 by Christine

chem 12
a) Calculate [H3O^+] in a 0.15M solution of benzonic acid, HC7H5O2(aq) having K of 6.4x10^-5. b) Calculate the per cent ionization of the HC7H5O2. I got.. Kb = [HC7H5O3][OH]/HC7H5O2 6.3x10^-5 x Kb =1.0x10^-14 Kb = 1.0x10^-14/6.3x10^-4 = 1.5x10^-10 1.5x10^-10 = (x)(x)/0.15 i'm ...
October 11, 2011 by Sarah

college
0.02 g of CaCO3 is dissolved in 1 L of water. Calculate the moles of calcium carbonate that have dissolved in the water, the moles of Ca2+ ions in solution, and the number of Ca2+ ions in solution?
January 27, 2010 by mike

Chemistry
0.02 g of CaCO3 is dissolved in 1 L of water. Calculate the moles of calcium carbonate that have dissolved in the water, the moles of Ca2+ ions in solution, and the number of Ca2+ ions in solution?
January 27, 2010 by mike

Chemistry
If you have 200 ml of a 0.1M solution of acetic acid (pka=4.75), 1. How many ml of a solution of 1.O M NaOH would you need to adjust the pH to 5.2? "Chemistry - DrBob222, Wednesday, June 29, 2011 at 8:41pm 200 mL x 0.1M = 20 mmoles. 1. ............HAc + OH^- ==> Ac^- H2O ...
June 30, 2011 by Brayden--help Dr. Bob

Chemistry
A sample of solid Ca(OH)2 is stirred in water at 30C until the solution contains as much dissolved Ca(OH)2 as it can hold. A 100.-mL sample of this solution is withdrawn and titrated with 5.00 X 10^-2 M HBr. It requires 48.8 mL of the acid solution for neutralization. What is...
February 17, 2010 by Candice

Chemistry
A 0.1300 g iron ore sample was dissolved in hydrochloric acid and the iron was obtained as Fe2+(aq). The iron solution was titrated with Ce4+ solution according to the balanced chemical reaction shown below. After calculation, it was found that 0.0259 g of iron from the ore ...
March 13, 2009 by Bob

algebra
a chemist needs 10 liters of a 25% acid solution. the solution is to be mixed from three solutions whose acid concentrations are 10% 20% 50% how may liters of each solution should the chmist use to satisfy the following? a use as little as possible of the 50% solution b use as...
April 26, 2008 by sandy

chem
Ionization energy is defined as the minimum energy required to remove an electron from the ground state (n0) to infinity (n∞). Determine the wavelength of radiation required to ionize the hydrogen electron from the n = 2 energy level. Calculate the energy (Joules) ...
October 2, 2006 by Mary

Chemistry
Predict the standard cell potential and calculate the standard reaction Gibbs free energy for galvanic cells having the following cell reactions: 2H2+O2=2H2O in acidic solution 2H2+O2=2H2O in basic solution I understand the idea behind the problem, but I am not sure how the ...
March 10, 2014 by Anonymous

Science
Chemistry Enthalpy Calculations? Given the equation: CaO + H2O ----> Ca(OH)2 A 1 g sample of CaO is dissolved in 100 ml water with density 1.00g/ml. The temperature rise is 3.7 degrees C. The specific heat is 4.00 J/g*deg. 1. Calculate the heat (in J) absorbed/given off by ...
October 18, 2012 by Pablo

chemistry
Which solutions are acidic? (Assume all solutions are at 25C. Kw = 1.0 x 10-14 at 25C.) A. A solution with [H+] = 9.4 x 10-6 B. A solution with [H+] = 5.5 x 10-10 C. A solution with pH = 6.1 D. A solution with [OH-] = 6.4 x 10-7 E. A solution with [OH-] = 2.0 x 10-6
October 8, 2010 by Ceci

statistics
given that u=100 X=91, s=27, and N=30 (a)calculate t. (b)write a sentence interpreting the value of t as a two- tailed test. (c)write a sentence interpreting the value of t as a one-tailed test.
April 24, 2011 by sassy

Solving Rational Equations
100mL of a solution contains 30 mL of acid; this is called a 30% acid solution because part 30 ---- = ---- = 0.30. whole 100 How many milliliters of acid x would need to be added to the solution to turn it into a 50% solution ? (HInt: Adding acid increases both the volume of ...
October 23, 2013 by Stacey

financial 200
Write a 200-300 word description of the four time value of money concepts: present value, present value of an annuity, future value, and future value of annuity. Descrive the characteristics of each concept and provide an example of when each of when each would be used.
July 23, 2010 by Chris

chemistry
A glucose solution contains 55.8g of glucose (C6H12O6) in 455g of water. Calculate the freezing poing and boiling point of the solution. (Assume a density of 1.00 g/ml for water. This what I did, I got moles of C6H12O6, 0.89 moles C6H12O6 then I got the mass of the solution ...
November 4, 2011 by Monique

Chemistry
I need help splitting this reaction into 1/2 reactions 3I2(s) + 2MnO2(s)+8 OH-(aq)<-> 6I-(aq) + 2MnO4-(aq) + 4H2O(l) Can you identify which components are oxidised, which are reduced and those that undergo no change? Can you identify which components are oxidised, which ...
April 19, 2007 by amy

ap chem
calculate the enthalpy of formationof solid MgOH2, given the following data: 2Mg(s) + O2(g)-> 2MgO(s) heat:-1203.6 Mg OH2(s) -> MgO(s) +H2O(l) heat: 37.1 2H2(g)+ O2(g) -> 2H2O(l) heat: -571.7 what equation would they want the three equations to develop into and which ...
October 4, 2007 by lily

chemistry
Calculate the concentration, in percent by mass, of a refrigerant brine solution which is 4.03 M in NaCl with a density of 1.116 g mL-1.
November 9, 2007 by keely

chemistry
Calculate the Ka of nitrous acid if a 0.200 mol/L solution at equilibrium at SATP has a percent ionization of 5.8%
April 5, 2008 by Laura

chemistry
Calculate how much energy will be released when 11.11g of calcium chloride are dissolved in 100ml of solution
May 2, 2009 by Mandy

chemistry
Commercial bleach contains 5.25% (by mass) of NaClO in water. It has a density of 1.08 g/mL. Calculate the molarity of this solution.
March 3, 2010 by Drew

Chemistry
Calculate the solubility of silver iodide in a 1.0 M sodium cyanide solution. Ksp = 8.5 x 10^-17 for AgI Kform = 2.5 x 10^5 for Ag(CN)2
April 7, 2010 by Erin

Chemistry
Calculate the freezing- and boiling-point changes for a solution containing 12.0 g of naphthalene (C10H8) in 50.0 g of benzene.
May 2, 2010 by Mariah

chemistry
calculate the percent composition or w/v% of 3x10 to the 2nd power mL solution containing 15g of glucose
May 4, 2010 by Quentin

chm
If 0.0490g of AgIO3 DISOLVES per liter of solution, calculate the solubility product constant.
June 27, 2010 by ami

Chemistry
What formula do I use to calculate the mass of KCl that is required to make 625 mL of a 0.200 M solution?
July 25, 2010 by Norma

College Chem
Calculate the number of grams required to make 250 mL of a 0.020 M KIO3 solution.
October 3, 2010 by Kelli

Chemistry
Calculate the freezing point of each of the solution 75.0 of glucose,C6H12O6 , added to 9.3010−2 of water.... Please help
December 6, 2010 by Garrett

Chemistry
Calculate the pH of a solution at the endpoint of a titration involving 25.00 mL of CH3COOH at unknown concentration, and 21.40 mL of 0.100 M NaOH
December 15, 2010 by Lisa

science
You add 12.5 mL of 4.15 acetic acid to 25.0 mL of 1.00 M NaOH. Calculate the hydronium ion concentration and pH of the resulting solution.
March 7, 2011 by Bill

chemistry
calculate the volume of 3M HCl needed to change the pH of 50 mL of the undiluted buffer solution by one pH unit?
March 16, 2011 by Anonymous

Genral chemistry
if you dissolve 1.60g of Cu(No3)2 in 100mL of water, calculate the molarity of the resulting solution ?
March 30, 2011 by Abdul

chemistry
For a solution that is 0.280M HC3H5O2 (propionic acid, Ka= 1.3*10^-5) and 0.0894M HI , calculate the following: [H3O+] [OH-] [C3H5O2-] [I-]
April 14, 2011 by Saunders

Chemistry
Calculate the molarity (M) of a solution of the strong acid HNO3 if the hydroxide ion concentration is 2.17E-12 M.
May 12, 2011 by Anonymous

Chemistry
5.85 g of sodium chloride(NaCl) is dissolved in 250 mL OF solution. Calculate mass percentage of the solute.
October 28, 2011 by Dewa

Chemistry
The osmotic pressure of a liquid at 320 K is 145 kPa. Calculate the freezing point of the solution.
November 29, 2011 by David

chemistry
Calculate the ionic strength of 100mM solution of Mg3(PO4)2 in 10 mM acetic buffer (CH3COONa)
December 14, 2011 by Nan

chem
calculate the amount of water that must be added to 6.5 grams of urea to produce a 22-2% by mass solution?
January 28, 2012 by anthoony

Chemistry
Calculate the [OH-] for a solution in which [H+] is 1000 times greater than [OH-]? and will the final result be acidic, basic, or neutral?
February 25, 2012 by Colin

Chemistry
Calculate the pH of a buffer solution obtained by dissolving 16.0 g of KH2PO4(s) and 27.0 g of Na2HPO4(s) in water and then diluting to 1.00 L. (pKa=7.21)
March 29, 2012 by Jematormal91

chemistry
Calculate the pH and percentage protonation of the solute in an aqueous solution of 0.39 M quinine if the pKa of its conjugate acid is 8.52.
April 24, 2012 by bob

Chemistry
Calculate the [H+] of a solution obtained by mixing 1 L of hydrochloric acid 1.0 M with 1 litre of sodium hydroxide 0.990 M.
May 11, 2012 by Katie

Chemistry
Calculate the amount (volume) of 0.135 M HClO4 solution required to neutralize 57.00 mL of .089 M NaOH
October 6, 2012 by Vicky

chemistry II
Calculate the grams in solute: 300 g of water in the preparation of 15.0% NaNO solution. Atomic Weight: Na=23,N=14,o=16.
December 17, 2012 by criss

Chemistry
Calculate the molality, molarity, and mole fraction of FeCl3 in a 39.2 mass % aqueous solution (d = 1.238 g/mL).
February 16, 2013 by Stevi

Chemistry
Calculate the pOH of an aqueous solution of 146.6 ml of 0.000625 M HBr(aq) after dilution to 850 ml.
March 21, 2013 by Mary Ann

Chemistry
Calculate the pOH of an aqueous solution of 146.6 ml of 0.000625 M HBr(aq) after dilution to 850 ml.
March 21, 2013 by Mary Ann

Chemistry
Calculate the pOH of an aqueous solution of 146.6 ml of 0.000625 M HBr(aq) after dilution to 850 ml.
March 21, 2013 by Mary Ann

Math
Calculate the morality of a solution made by mixing 250ml of 0.75M H2SO4 with 400ml of 2.5MH2SO4
March 26, 2013 by Alica

chemistry
Calculate the concentrations of all species present C6H5N2, C6H5NH3+ OH^-, and H3O^+}) in a 0.14 M solution of aniline.
April 5, 2013 by kim

chemistry
calculate the enthalpy of mixing for the solution of 10% platinum and 90% gold .express your answer in units of kg/mole
May 7, 2013 by himani.

Chemistry
A solution contains 80.0 g of sodium chloride and 400.0 g of water. Calculate the NaCl as a mass percentage
June 2, 2013 by Monica

chemistry
Calculate the molarity (M) of a solution of the strong base RbOH if the hydroxide ion concentration is 0.000309 M.
October 10, 2013 by HELP ASAP PLEASE

chemistry
Calculate the molarity (M) of a solution of the strong acid H2SO4 if the hydrogen ion concentration is 0.000244 M.
October 10, 2013 by HELP ASAP PLEASE

Chemistry
Dr bob for this question :Calculate the molar solubility of manganese II hydroxide in ph 12.85 solution. The Ksp is 2.1 x 10^-13 but I can't solve for x thanks.
May 26, 2014 by Anonymous

chemistry
calculate the mass of Cuso4.5H2O required to prepare 500 cm3 of a 0.400 m/dm-3 solution
June 8, 2014 by alice

science
calculate the mass of Cuso4.5H2O required to prepare 500 cm3 of a 0.400 m/dm-3 solution
June 8, 2014 by alice

chemistry, biology
Calculate the pH of a solution obtained by adding 20 mL of .2M KOH to 480 mL to .02M isoelectric glycine
July 6, 2014 by Laurel

chemistry
calculate the molality, molarity, and mole fraction of NH3 in an 12.80 mass % aqueous solution (d=0.9651 g/ml)
September 8, 2014 by maria

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