Wednesday

May 25, 2016
Number of results: 59,517

**chemistry**

Calculate the pH of an Aqueous 3.8 x 10^-5 M solution of barium hydroxide. I need help.
*August 21, 2012 by Vincent*

**chemistry**

Calculate the molality of CsCl in a 19% by mass aqueous solution.
*September 13, 2012 by cheri*

**Science**

calculate the solubility of NaCl in a solution which contains 0.1 M CaCl2
*October 12, 2012 by Tejpal Chandrakar*

**chemistry**

0.30M nh3 and 0.20M HCL calculate the ph of solution kb=1.8 × 10^-5
*March 2, 2013 by kanks*

**general chemistry**

Calculate the molarity of each of the following solutions.70.8 in 2.51 of solution
*March 7, 2013 by kelia*

**Chemistry**

Calculate the pH of a buffer solution that contains 0.60 M NaH2PO4, and 0.26 M Na2HPO4.
*April 14, 2013 by Maddie*

**chemistry**

im so confused about this question Calculate the pH of a solution that has [H3O+] = 5.5 x 10-3.
*April 29, 2013 by joe *

**chemistry**

calculate the molarity of 29.25 grams of NaCl in 2.0 liters of solution
*May 28, 2013 by Anonymous*

**Chemistry**

Calculate the permanganate activity in an aqueous 0.18 M KMnO4 solution.
*August 12, 2013 by RC*

**Chemistry**

3.50 g of NH4Cl is added to 18.8 g of water. Calculate the molality of the solution.
*October 16, 2013 by Shardai*

**chemistry**

8.90 g of NH4Cl is added to 19.7 g of water. Calculate the molality of the solution
*November 7, 2013 by Anonymous*

**ap chemistry**

Calculate the ratio of [NH3]/[NH4+] that gives a solution of pH = 10.60.
*February 4, 2014 by gabriella*

**Ap chem-Bases**

Calculate the pH of a 0.2M solution of Triethylamine, (C2H5)3N, with a Kb of 4.0x10^-4
*February 16, 2014 by Jessica*

**Ap chem-Bases**

Calculate the pH of a 0.2M solution of Triethylamine, (C2H5)3N, with a Kb of 4.0x10^-4
*February 17, 2014 by Jessica*

**Chemistry**

A solution formed by dissolving an antacid tablet has a pH of 9.18. Calculate [H+].
*April 27, 2014 by Anonymous*

**Chemistry**

A solution formed by dissolving an antacid tablet has a pH of 9.18. Calculate [H+].
*April 27, 2014 by Anonymous*

**Chemistry**

Calculate the molar solubility of manganese II hydroxide in ph 12.85 solution.
*May 26, 2014 by Anonymous *

**Science**

Calculate the hydroxide ion of a solution of almond extracted of PH 3.8
*June 6, 2014 by Debora*

**Chemistry**

Calculate the pH of a 1.19M sodium formate, HCOONa, solution.
*November 23, 2014 by Bill*

**Chemistry 120**

Calculate the pH of aqueous solution 0.0000019 M KOH
*December 15, 2014 by David Allen*

**Chemistry**

Calculate the pH and concentration of H3O of a 0.285M HCl solution.
*January 22, 2015 by Kat*

**Chemistry**

Calculate the pH of a solution that is 0.185M in HC2H3O2 and 0.125M in KC2H3O2
*March 6, 2015 by Gabby*

**Chemistry**

Calculate pH of a solution that is 0.255M in CH3NH2 and 0.105M in CH3NH3Br
*March 6, 2015 by Gabby*

**science**

Calculate the PH of the 0.4g of NaoH in water to give 200ml of solution
*December 15, 2015 by praful*

**chemistry 12u**

how do i calculate this.. a solution of nitrous acid has a pH of 2.73 what is the [H3O+] ?
*May 10, 2016 by julie*

**Finance**

Benson Incorporated has bonds with the following features par value of 1000.00 maturity is 10%. Determine if the bond sells for a premium, par, or discount and explain your answer. Calculate the value of the bond if interest is paid on an annual basis versus a semi annual ...
*February 6, 2012 by howard*

**chemistry**

A student prepares a solution of hydrochloric acid that is approximately 0.1 M and wanted to determine its precise concentration. A 25.00 mL portion of the HCl solution is transferred to a flask, and after a few drops of indicator are added, the HCl solution is titrated with 0...
*June 14, 2015 by walter*

**Algebra 1 **

Solve each equation. Rewrite the equation as two cases. 1). The absolute value of x - 2 minus 3 equals 5. A: I know one of the solutions is 10. However, I do not believe there is a second solution. 2). The absolute value of x + 7 increased by 2 = 10. A: I know one of the ...
*October 2, 2013 by Anonymous*

**Chemistry- please check my work**

Question: The following equilibrium was studied by analyzing the equilibrium mixture for the amount of HCL produced. LaCl3(s)+ H2O(g) goes to LaOCl(s)+2HCl(g). A vessel whose volume was 1.25L was filled with 0.0125 mol of lanthanum (III)chloride and 0.0250 mol H2O. After the ...
*February 25, 2009 by eliz*

**chemistry**

calculate the concentration of each solutions: 3 moles of solute dissolved in 2 liter of solution 6 moles of solute dissolved on 9 liters of solution 4 moles of solute dissolved in 3 liters of solution
*March 29, 2010 by jess*

**Chemistry **

How would one work through this problem? -Calculate the number of liters of 1.25M solution that can be made from 6.400g of barium nitrate. - I know that it's just stoichiometry, but I'm confused. The formula for molarity is the number of moles of the solute divided by liters ...
*May 7, 2016 by Charlie*

**CHEM**

A 0.552 g sample of ascorbic acid(Vitamin C) was dissolved in water to a total volume of 20.0 ml and titrated with 0.1103 M KOH. The equivalence point occurred at 28.42 ml. The pH of the solution at 10.0 ml of added base was 3.72. From this data, determine the molar mass and ...
*March 21, 2012 by Cooper*

**Chemistry**

1.) Watch the animation, and observe the titration process using a standard 0.100 M sodium hydroxide solution to titrate 50.0 mL of a 0.100 M hydrochloric acid solution. Identify which of the following statements regarding acid-base titrations are correct Drag items A-F to: ...
*November 19, 2015 by LuigiR*

**Statistics for Business**

Consider the following sample of data: 11.2, 28.4, 32.6, 17, 13.5, 2.2, 38, 41.4, 1.9, 14.4, 21.8, 23.8 a) Calculate the max, min, Q1, median, and Q3 b) Calculate the average c) Calculate the standard deviation d) Calculate the variance
*January 19, 2014 by thomas*

**Chemistry**

Question from text: "The reaction between phosphorus and chlorine is described by the equation, P4(s) + 6 Cl2(g) ↔ 4 PCl3(l). At equilibrium, the concentration of Cl2 is found to be 0.87 M. Calculate Keq." Keq = [PCl3]^4 / [P4] [Cl2]^6 I am not seeing how to solve this ...
*January 28, 2016 by Jennifer*

**Chemistry**

A solution containing excess lead(ii) nitrate is reacted with 380.0ML of 0.250mol/L potassium iodide solution. A bright yellow Precipitate is of lead(ii) iodide is formed. Calculate the mass of lead (ii) iodide that should be formed. Pb(NO3)2+2KI-> 2KNO3+PbI2
*June 17, 2015 by Robyn*

**Chemistry**

a solution of 0.2113 g of water dissolv ed in 25g of a solvent freezes at 11.5 degrees celcius below the freezing point of the solvent. what is the Kf for the solvent? A)0.735 B)1.36 c)5.39 D)24.5 Help!!! delta T = Kf*molality Calculate molality = #mols solute/kg solvent, plug...
*April 27, 2007 by natali*

**Chemistry, help!**

how do you calculate this: Calculate the mass of copper needed to displace 5.0g of silver from silver nitrate solution. (Relative Atomic Masses: Ag=108, Cu=63.5) Eqn=Cu+2AgNO3->Cu(NO3)2+2Ag How do you write a half equation? Complete the half equation to show the oxidising ...
*January 20, 2008 by Anonymous*

**chemistry**

Calculate the enthalpy of change, Delta H of rxn, for each of the reactions. record the values in the data table part 2 I calculated the heat of rxn of the HCl +NaOH------NaCl + H2O. How do i go from here to enthalpy of change
*January 8, 2012 by AP Chemistry Question*

**Chemistry**

Calculate the mass of baking soda, NaHCO3, needed to neutralize 3.0 mL of 3.0 M hydrochloric acid, HCl(aq). Ok, so I'm super confused. I have the equation, but I'm stuck with what to do with it. Equation: NaHCO3 + HCL --> NaCl + H2O + CO2
*February 27, 2013 by Sarah*

**Chemistry**

When 9.08 times 10^5 grams (one ton) of sodium chloride are electrolyzed in the commerical production of Chlorine, 5.24 times 10^5 grams of Chlorine are produced: 2 NaCl (aq) + 2 H2O (l) >>H2 (g) + Cl2 (g) + 2 NaOH (aq). Calculate the percentage yield.
*June 10, 2013 by Shane*

**Chemistry**

When 9.08 times 10^5 grams (one ton) of sodium chloride are electrolyzed in the commerical production of Chlorine, 5.24 times 10^5 grams of Chlorine are produced: 2 NaCl (aq) + 2 H2O (l) >>H2 (g) + Cl2 (g) + 2 NaOH (aq). Calculate the percentage yield.
*June 10, 2013 by Shane*

**chemistry**

How to find moles given oxidation numbers and chemical formula? Trying to do my chemistry lab but i'm super duper stuck. please help me i'm gonna die. this is the part i'm stuck on: The overall charge on the complex, [Ni(en)(H2O)]^2+ * SO4^2- * H2O is zero; the charge on ...
*November 15, 2012 by dr bob's number one fan*

**Chemistry**

IN the polystyrene beaker, mix 20mL of 0.1 M Acetic acid and 25mL of 0.1M Sodium Acetate and immediately measure the pH. Remove the electrode and add 5ml of 0.1 M HCl to this buffer. Stir the solution and measure the pH. _______________ INFO: concentration of acetic acid= 0.1M...
*March 28, 2010 by Saira*

**Science**

How much sodium hydroxide, at what concentration, do I need to add to 500 mL of 0.1 N HCL to obtain pH 6.8. How do you calculate this? pH = -log(H^+) M HCl = N HCl mols = M x L. After you know mols HCl you have, then make a solution of NaOH and calculate how much of that must ...
*February 5, 2007 by Ruby*

**Algebra**

How do you solve the following problem? 3(4+4x)= 12x+2 It has no solution. X can be any value, and it wont equal.
*April 10, 2007 by James*

**absolute value**

|8m+7|=9 8m+7=-9 or 8m+7=9 -7=-7 -7=-7 8m/8=-16/8 8m/m=2/8 m=-2 m=1/4 the solution set is {-2, 1/4} Is this correct or do I need to go further or completely wrong!
*March 21, 2008 by Kally*

**college**

Which of the following choices is a solution for: (-3-i)x1 + (1-2i)x2 = 0 (-7-9i)x1 + (7-4i)x2 = 0 for any value of the variable t [x1] = ? [x2] A: [5] [1+7i] * t B: [5] [1-7i] * t C: [5] [-1-7i] * t D: [5] [-1+7i] * t This is linear algebra by the way;
*December 4, 2009 by Michael*

**Chemistry**

A 0.490 M solution of an unknown monoprotic weak acid, HA, is 2.80% ionized. What is the value of Ka for HA?
*April 5, 2010 by Jenny*

**Math**

Determine the value(s)of k that give the type of solution indicated: 2x^2+5x-2(k-1)=0. Show your work.
*September 14, 2010 by Mr. Seuss*

**Algebra-please check**

What is the solution for absolute value of -1 + x = 5 I think the two solutions are x = 6 and x = (-4)
*October 6, 2010 by Tanya*

**Algebra**

Using the substitution method, what is the value of a in the solution to the system of equations below? a=3b+7 4a+9b=70
*March 31, 2013 by Angie*

**math**

find the value of k such that the equation e^(2x)=krootx has exactly one solution.
*April 4, 2013 by tom*

**Algebra**

2. What is the value of x in the solution to the system of equations below? 15x – 12y = 13 30x + 9y = 4
*February 4, 2016 by Astral Tellurian*

**chemistry**

A student generates H2(g) over water using the reaction between zinc and hydrochloric acid Zn(s)+ 2HCl(aq)---> ZnCl2(aq)+ H2(g) Data: Mass of vial and zinc 15.5082 mass of vial 15.3972 mass of zinc 0.111 final burette reading 45.30mL barometric pressure: Patm 100.6kPa ...
*November 23, 2011 by Yuli*

**physics**

Two crates A and B connected together by a light rope are pulled along a factory floor by an applied force, F. Crate A has a mass of 50 kg and the coefficient of friction (μ) between crate A and the floor is 0,25. Crate B has a mass of 35 kg and μ between B and the ...
*June 3, 2012 by Nick*

**Statistics:Z and T Statistics: Confidence Interva**

Z and T Statistics: Confidence Intervals and Significance Tests: A friend who hears that you are taking a statistics course asks for help with a specific chemistry lab report. She has made four independent measurements of the specific gravity of a compound. The results are : 4...
*September 11, 2007 by Carma*

**chemistry**

if it requires 35.0 milliliters of 0.50 molar NaOH to neutralize 25.0 milliliters of HCl, what is the concentration of the HCl solution? Balanced equation: NaOH + HCl yields NaCl + H2O
*November 17, 2010 by smith*

**chemistry**

If it requires 30.0 milliliters of 1.2 molar HCl to neutralize 20.0 milliliters of NaOH, what is the concentration of the NaOH solution? Balanced equation: NaOH + HCl NaCl + H2O (3 points)
*June 22, 2011 by Anonymous*

**maths **

another question ? A is an acute angle and sin A=3/5 calculate the value of tan A ??
*February 8, 2010 by Amy*

**calculus**

to the nearest metre x=24m and y=6m. Calculate the upper bound for the value of xy
*May 10, 2010 by Anonymous*

**AP CHEMISTRY**

The Kb for ammonia (NH3) at 25°C is 1.8* 10-5. By using the value of Kb, calculate ΔG° for the equilibrium
*March 23, 2012 by DAN*

**math**

The 2nd, 3rd and 4th term of an ap are x-2,5,x+2 respectively ,calculate the value of x
*March 30, 2012 by wale2*

**chemical equilibrium**

Calculate the value of Kc for 4NH3(g) + 3O2(g)= 2N2(g) + 6H2O(l)
*July 9, 2012 by mohamed*

**math**

Interest= $432 r=6% t=8 years How do I calculate the principal and future value?
*July 28, 2012 by LaCresha*

**chemistry**

calculate the value of the equilibrium constant K for this reaction A+B <--> C from the following information 3C <--> D Kc= 7.1*10^-4 D <--> 3A + 3B Kc= 2.9*10^-2
*November 3, 2012 by Brun*

**physics**

calculate the value of g at a height of 3600 km above the surface of the earth?
*December 12, 2012 by aish*

**Science**

Calculate the wavelength of a photon with energy 2.45 eV. Enter the numerical value in m
*March 2, 2013 by Anonymous*

**Science**

Calculate the wavelength of a proton with energy 2.45 eV. Enter the numerical value in m
*March 2, 2013 by Anonymous*

**ut**

The acidity constant of acetic acid is 1.8 × 10-5. Calculate the % error of the measured Ka value.
*October 31, 2013 by Anonymous*

**Math**

The first three terms of an arithmetic progression are t, 2t-1, 2t+4. Calculate the value of t.
*July 2, 2014 by Christopher*

**Chemistry**

Calculate the value of ΔS when 1.10mol of Br2(l) is vaporized at 58.8 ∘C
*April 2, 2015 by Austin*

**Chemistry**

A goal of the acid-base titration in this scenario is to determine the concentration of sodium hydroxide solution. To do this, a 1.3000 g sample of potassium hydrogen phthalate (KHC8H4O4) is massed out. The KHP has one acid proton (H+). The solid is dissolved in a beaker and 2...
*September 26, 2015 by Seth*

**Chemistry**

A 1.00% by mass MgSO4 solution has a freezing point of -.192°C. Water has a Kf of 1.86 (KxKg)/mol. a.) Estimate the van’t Hoff i factor from the data. b.)Determine the total molality of all solute species. c.) Calculate the percentage dissociation of MgSO4 in this solution. I ...
*January 27, 2014 by Anonymous*

**Chemistry lab**

A 1.340gram sample of an unknown acid, H3A, was placed in a 250.0 mL volumetric flask and diluted to volume with water. A 45.35 mL sample of this acid solution was titrated with 37.77 mL of a 0.1006M NaOH solution. A) Using one set - up dimensional analysis B) Calculate the ...
*March 22, 2016 by Stacy*

**Chemistry**

When 0.969 g of CaO is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 397C 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. Delta Hrxn, for the reaction of CaO(s) + 2H+(aq) Ca2+(aq) + ...
*February 24, 2008 by Anonymous*

**chem-help pls!**

When 0.975 g of CaO is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 400C 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. Hrxn, for the reaction of CaO(s) + 2H+(aq) Ca2+(aq) + H2O(l) ...
*February 25, 2008 by Anonymous*

**Algebra 1**

A restaurant has one type of lemonade that has 12% sugar and another that is 7% sugar. How many gallons of each does the restaurant need to make 20 gallons of a lemonade mixture that is 10% sugar? a. 12 gallons of the 12% lemonade and 8 gallons of the 7% lemonade. b.10 gallons...
*January 5, 2016 by rachel.*

**Chemistry**

What is the vapor pressure at 23 degree C of a solution of 1.20g of naphthalene, C10H8 in 25.6 g of benzene, C6H6? The vapor pressure of naphthalene can be neglected. Calculate the vapor-pressure lowering the solution
*February 7, 2008 by Lauren*

**Analytical CHM**

Calculate the theoretical amounts of 0.1000 M NaOH titrant used to titrate 0.8 and 0.9 g KHP Please show step by step solution , i need the correct significant figures and units to finish up the rest of the lab correctly i found the answer but for some reason ,using my answers...
*September 15, 2014 by Jessy*

**Chemistry**

Exactly 100 mL of 0.14 M nitrous acid (HNO2) are titrated with a 0.14 M NaOH solution. Calculate the pH for the following. (a) the initial solution (b) the point at which 80 mL of the base has been added (c) the equivalence point (d) the point at which 105 mL of the base has ...
*March 17, 2012 by Tanya*

**Chemistry 2**

Calculate the molarity of the following aqueous solution of 25.0 grams of MgBr2 in 0.355 L solution? Did I work this right? 25gMgBr2/184.113 gMgBr2 =.1357861748 mol MgBr2 then: .1357861748 mol MgBr2/0.355 L =.382 M
*August 8, 2014 by Brandi *

**Chemistry**

What is the molarity of HCL if it takes 16.5 mL of 0.100 M NaOH to titrate 10.0 mL of HCl? HCl + NaOH -> H2O + NaCl molarity = moles of solute/liters of solution
*September 18, 2014 by Selena*

**Chemistry 30**

A mixture of 2.5 moles of H2O and 100 g of C are placed in a 50.0 L container and allowed to come to equilibrium in the following reaction: C(s) + H2O(g) CO(g) + H2(g) The equilibrium concentration of hydrogen gas is found to be 0.040 M. What is the ...
*September 30, 2014 by Ade*

**Chem**

A mixture of 2.5 moles of H2O and 100 g of C are placed in a 50.0 L container and allowed to come to equilibrium in the following reaction: C(s) + H2O(g) CO(g) + H2(g) The equilibrium concentration of hydrogen gas is found to be 0.040 M. What is the ...
*October 3, 2014 by Ade*

**Stats**

2 samples were collected to determine whether there was a difference between two weight loss methods targeting men. The average weight loss method is provided for the 2 samples along with the respective standard deviations. Is the second method - with an average weight loss of...
*February 23, 2007 by Jason L*

**statistics**

You randomly choose 16 unfurnished one-bedroom apartments from a large number of advertisements in your local newspaper. You calculate that their mean monthly rent is $613 and their standard deviation is $96. Does this SRS give good reason to believe that the mean rent of all ...
*November 19, 2013 by arshi*

**math**

You randomly choose 16 unfurnished one-bedroom apartments from a large number of advertisements in your local newspaper. You calculate that their mean monthly rent is $613 and their standard deviation is $96. Does this SRS give good reason to believe that the mean rent of all ...
*November 19, 2013 by arshi*

**chem--need help, please!!!**

Ka for benzoic acid, C6H5COOH, 6.5x10^-5. Calculate the pH of solution after addition of 10.0, 20.0, 30.0, and 40.0 mL of 0.10 M NaOH to 40.0 mL of 0.10 M Benzoic acid. PLEASE CHECK MY ANSWER!!!!! My answer is: Moles acid = 0.040 L x 0.10 M = 0.0040 Moles base = 0.010 L x 0.10...
*October 20, 2010 by Andy *

**Chemistry**

The maximum solubility of silver sulfate, Ag2SO4 [molar mass = 312], is 4.50 g/L at 25°C. Silver sulfate dissociates by the reaction below: Ag2SO4(s) <--> 2 Ag+ (aq)+ SO4¯² (aq) 1.What are the [Ag+] and [SO4¯²] in a saturated solution of silver sulfate made by dissolving...
*March 20, 2011 by Paul*

**Chem6**

A solution contains naphthalene dissolved in hexane at a concentration of 10.40% naphthalene by mass. Calculate the vapor pressure of hexane above the solution, given that the vapor pressure of pure hexane at this temperature is 151 torr.
*May 2, 2011 by Ryan*

**chemistry**

A sample of water is found to contain 0.059 ppm of Pb2+ ions. Calculate the mass of lead ions per liter of this solution (assume the density of the water solution is 1.0 g/mL) 1.2E-2 g/L Pb2+ 5.9E-8 g/L Pb2+ 5.9E-5 g/L Pb2+ 1.2E-5 g/L Pb2+ 2.9E-10 g/L Pb2+
*February 5, 2012 by Heaton*

**chemistry**

( from the previous chemistry question)hydration just means H2O would attach to the ions, right? would the H2O attach to the -F to form larger molecules? how does the entropy change from that?
*April 19, 2010 by carla*

**Urgent Chemistry**

The diffusion current for a standard is 1 x 10^-4M solution of hydroquinone is 17.5 microamperes. An unknown solution of hydroquinone, when diluted hundred folds and polarographed under same conditions yielded a current of 30.5 microamperes. Calculate the concentration of ...
*August 4, 2015 by Adeola*

**chemistry**

Consider the gold-platinum system which has a value of delta w of -4250 J/mole; (a) Calculate the enthalpy of mixing for a solution of 10% platinum and 90% gold. Express your answer in units of kJ/mole. (b) Is the dissolution of 10% platinum into gold an endothermic or an ...
*May 4, 2013 by ssss*

**Math**

Sorry I wasn't finished with the problem. Fijisawa Inc. is considering a major expansion of its product line and has estimated the following cash flows associated with such an expansion. The initial outlay would be $1,980,000, and the project would generate incremental free ...
*June 15, 2015 by Alicia*

**Chemistry**

Hello, i seem to be stuck on a problem and do'nt know why im not gettin the right answer.I have the he Ka and Kb values for each of the weak acids and bases from the chart and I keep getting zero and the second one 2.27*10^-24 is this correct?? Thank uu Solve an equilibrium ...
*March 24, 2011 by Amy Wight*

**Chemistry**

Hello, i seem to be stuck on a problem and do'nt know why im not gettin the right answer.I have the he Ka and Kb values for each of the weak acids and bases from the chart and I keep getting zero and the second one 2.27*10^-24 is this correct?? Thank uu Solve an equilibrium ...
*March 24, 2011 by Amy Wight*

**Chemistry**

Hello, i seem to be stuck on a problem and do'nt know why im not gettin the right answer.I have the he Ka and Kb values for each of the weak acids and bases from the chart and I keep getting zero and the second one 2.27*10^-24 is this correct?? Thank uu Solve an equilibrium ...
*March 24, 2011 by Amy Wight*

**Managerial Economics**

Consider the Linear demand function Q = 20 - 0.5P c- Using calculus, find the level of output, Qrmax, where total revenue reaches its maximum value. What price Prmx maximizes total revenue? What is the value of TR at this maximum point. d- Write the equation for marginal ...
*March 12, 2013 by alejandro guzman*