Sunday

January 22, 2017
Number of results: 21,730

**need help please**

solve each system graphically. be sure to check your solution. if a system has an infinite number of solutions, use the set-builder notation to write solution set. if a system has no solution, state this. where appropriate, round to the nearest hundredth. 6x-2y=2 9x-3y=1

*December 7, 2011 by Mandy*

**Algebra**

How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an equation? If you replace the equal sign of an equation and put an inequality sign in its place, is there ever a time when the same value will be a ...

*April 15, 2008 by will*

**Chemistry - University**

Pentane (C5H12) and hexane (C6H14) form an ideal solution. The vapour pressure of pentane at 25oC is 511 mmHg and that for hexane is 150 mmHg. A solution is prepared by mixing pentane (density = 0.63 g/mL) and hexane (density = 0.66 g/mL). The mole fraction of hexane in the ...

*December 9, 2014 by Gab*

**science(chem)**

Commercial hydrazine is sold as a 64% solution. Using that as your starting material, how would you prepare a 5% solution of hydrazine? well if it is sold as 64% solution would that mean that it has 64g of hydrazine per 100ml of solvent(water)? and what they want in the end is...

*May 4, 2008 by ~christina~*

**chemistry**

If you add a metal piece to excess acid, what of listed factors below will increase, decrease, or have no impact on how fast a reaction happens? a) lower molarity (concentration) of a solution b) higher molarity (concentration)of a solution c) increase volume of a solution (...

*May 22, 2013 by K*

**chemistry**

A 2.500×10−2M solution of NaCl in water is at 20.0∘C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.3mL . The density of water at 20.0...

*May 24, 2015 by Jason*

**chemistry**

A 2.500×10−2M solution of NaCl in water is at 20.0∘C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.3mL . The density of water at 20.0...

*May 24, 2015 by Jason*

**College Chemistry**

You weigh a sample of a monoprotic unknown acid and dissolve it in 50.00 mL of distilled water. Exactly half of this solution is titrated with Sodium Hydroxide to the phenolphthalein end point. The pH of the other half of the original solution is measured with a pH meter. The...

*April 9, 2013 by Kim*

**chemistry**

When an aqueous solution suspected of containing Ba2+ or Pb2+ or both are mixed with sulfuric acid a precipitate forms. in another test, when the original solution is mixed with an aqueous solution of sodium sulfide no precipitate forms. What do these two tests indicate about ...

*October 16, 2008 by Lili****

**HELP!! Chemistry**

Round your answer to the correct number of significant digits and show work. 1. How many grams of NaI would be used to produce a 2.0 M solution with a volume of 10.00 L? 2. What is the molarity of a 2.50 x 102 cm3 solution containing 450.0 g of C6H12O6 ? 3. How many moles of ...

*September 26, 2013 by _Unknown*

**Algebra 116**

I need help with these algebra problems please. 1.Solve by using the substitution method. a. 8x - 3y =-61 7x + 68 = y What is the solution system _____? b. 4m + n =27 m - 2n = 9 What is the solution system_______? c. 8x + 9y = -15 -6x + y = 19 What is the solution System______...

*September 16, 2008 by MzMaria*

**chem lab**

when an aqueous solution suspected of containing BA2+ or Pb2+ or both is mixed with sulfuric acid a precipitate forms. In another test, when the original solution is mixed with an aqueous solution of sodium sulfide no precipitate forms. What do these two tests indicate about ...

*March 25, 2008 by natash*

**chemistry**

1.Does a pH of 8.6 describe a solution with a higher or lower hydronium ion concentration compared to a neutral solution? Is such as solution called acidic or basic? 2. Compared to a neutral solution, would you expect an acidic solution to have a higher or lower pH and a ...

*May 2, 2013 by alex*

**chemistry**

A solution is prepared by dissolving 10.00 grams of a monobasic salt in a total volume of 1.00 litres. The pH of this solution was measured at 13.07 and a conductivity experiment determined that this salt was completely ionized in solution. What is the molecular weight of this...

*January 29, 2014 by Temmi*

**Chemistry**

In a similar experiment, a sample of tin metal was dissolved in nitric acid to produce 23.00 mL of solution containing Sn2+. Titration analysis resulted in the calculation that the concentration of Sn2+ in this solution was 0.65 mol/L. b. What mass of tin was used to make the ...

*November 5, 2016 by james*

**Biochemistry**

BSA stock solution A has a concentration of 3.50 mg/mL. 1.00mL of stock solution A is diluted to a final volume of 5.00mL to prepare solution B. 1.00mL of stock solution B is diluted to a final volume of 5.00mL to prepare solution C. 1.00mL of stock solution C is diluted to a ...

*November 18, 2013 by S*

**biology**

2more questionsss ! dats it ! 1. Which statement is TRUE? a. A cell placed in an isotomic solution will swell. b. A cell placed in a hypotonic solution will swell. c. A cell placed in a hypotonic solution will shrink. d. A cell placed in a hypertonic soluction will remain the ...

*June 24, 2011 by akim*

**chem**

An aspirin tablet weighing 0.650 g has been analyzed and contains 68.2 % ASA (180.16 g/mol) by mass. A student dissolved the tablet in hot NaOH and the cooled solution was diluted with DI water to the mark in a 250 mL volumetric flask. Exactly 3.00 mL of the solution was ...

*April 20, 2008 by un*

**Chemistry**

A solution of I2 was standardized with ascorbic acid. Using a .1000 g sample of pure ascorbic acid, 25.32 mL of I2 were required to reach the starch end point. A. What is the molarity of the iodine solution? B. What is the titer of the iodine solution?

*November 10, 2010 by Candy*

**Chemistry**

A solution of I2 was standardized with ascorbic acid. Using a .1000 g sample of pure ascorbic acid, 25.32 mL of I2 were required to reach the starch end point. A. What is the molarity of the iodine solution? B. What is the titer of the iodine solution?

*November 10, 2010 by Candy*

**Chemistry**

How many grams of nickel (II) sulfate hexahydrate would be present in one liter of a 0.40 molar solution? (Hint: a 1.0 molar solution would have 1 mole of NiSO4*6H2O per liter of solution)

*April 10, 2011 by Jon*

**Chemistry**

1.Calculate the pH of a solution prepared by mixing 20mL of the .07222M aspirin solution with 10mL of .2M NaOH. 2. Calculate the pH for the titration of 40mL of .1M solution of C2H5NH2 with .1M HCl for a)0 mL added and b)20 mL added c)40 mL added d)50mL added. Kb= 6.4x10^-4

*November 26, 2011 by Jessica*

**Chemistry**

If your solution’s final volume of 32.55 mL yields 3.6 grams of AgCl, determine the Molarity of the final solution. Also, how many milliliters of a 1.85 M solution of AgNO3 did you add to an excess of aqueous NaCl to provide the 3.6 grams of AgCl?

*March 26, 2013 by Shoba*

**Science**

what test would you need to perform to prove that it is the combination of glucose in the glucose indicator solution that changes color when heated and not just the glucose or the glucose indicator solution alone. support your anwser with a solution

*October 14, 2013 by Guest*

**Chemistry**

Calculate the osmotic pressure of this solution. 18..6 grams of solute with molecular mass of 8940 grams are dissolved in enough water to make 1.00 dm3 of solution at 25 celsius. What is the osmotic pressure of the solution?

*November 22, 2010 by Jose Reyes*

**chemistry**

Describe how a 250.0 mL aqueous solution of 1.50 M MgCl2 is prepared from a stock solution of 6.00 M MgCl2. ANSWER: Measure 62.5 mL of the stock solution into a container and dilute to 250.0 mL so what i need explained is where did 62.5 mL come from?

*December 13, 2010 by Stacy*

**Chemistry**

A: A student must make a five-fold dilution of a 2.15 M HCl solution. If the student wishes to make 75.0 mL of the diluted solution, what volume of the 2.15 M solution will he need to dilute? B: What is the concentration of the diluted substance?

*March 21, 2011 by Anonymous*

**Chemistry**

A 16.6 mL portion of an HBr solution of unknown strength is diluted to exactly 247 mL. If 102.1 mL of this diluted solution requires 87.8 mL of 0.37 M NaOH to achieve complete neutralization, what was the strength of the original HBr solution?

*May 1, 2011 by Sam*

**Chemistry**

What volume of 0.200M of aqueous solution of formic acid, a weak monoprotic acid (KA = 1.78x10-4) and 0.200M aqueous solution of NaOH would you mix to prepare a 500mL of a buffer solution of pH = 4.0.

*September 26, 2012 by Sam*

**Chemistry**

If a solution of formic acid contains 0.2 M HCHO2, 0.006 M CHO2-, and 0.006 M H+, What is the Ka of the acid? What is the ph of the solution at the concentrations given? What would happen to the equilibrium position if more CHO2- were added to the solution?

*July 7, 2014 by Anonymous*

**chemistry 121**

If a solution of 0.5 M HOAc dissociates as follows: HOAc + H2O „® H3O+ + OAc-, what is the final [H3O+] in the solution? Ka for HOAc = 1.8„ª10-5. What is the pH of the above solution? What is the Kb for HOAc? not sure of the initial set up please help

*May 5, 2015 by Nicole*

**chemistry**

Determine the mole fraction of lithium bromate in a 6.32 M aqueous solution of lithium bromate. The density of the solution is 1.16 g mL-1. I understand that 6.32 M of solution= mols of the compound. I multiplied 1000mL by the density to get grams. I don't know what to do next.

*November 15, 2016 by everest*

**Chemistry**

A solution contains the following ions: Hg2(2+) and Fe(2+). When potassium chloride is added to the solution, a precipitate forms. The precipitate is filtered off and potassium sulfate is added to the remaining solution, producing no precipitate. When potassium carbonate is ...

*October 1, 2010 by June*

**Simple Chemistry**

A.Write a brief procedure outling how would you prepare 250mL of a 0.150M solution of a CoCl2 from solid CoCl2 and distilled water b. Using the solution from part a and distilled water, how would you prepare 100ml of a 0.0600 M solution of CoCl2 C. What absorbance would you ...

*April 28, 2014 by Armando*

**chemistry Thank a lot help**

100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final density 1.25g/ml. 50ml of 20.8% bacl2 and 100ml of 9.8% h2s04 solution are mixed. Molarity of cl ions in the resulting solution is ...

*November 22, 2014 by Ken*

**chemistry help**

A 15.00 mL sample of an unknown monoprotic weak acid solution is titrated with 0.35 M NaOH. The initial buret reading is 0.23 mL. The phenolphthalein indicator turns the solution light pink when the buret reads 29.58 mL. B. How many moles of NaOH were delivered? C. How many ...

*April 1, 2015 by jk*

**MATH**

A pharmacist mixed some 10%-saline solution with some 15%-saline solution to obtain 100 mL of a 12%-saline solution. How much of the 10%-saline solution did the pharmacist use in the mixture? A 60 mL B 45 mL C 40 mL D 25 mL CAN SOME GIVE AN EQUATION TO HELP MY SOLVE THIS ...

*May 7, 2010 by Anonymous*

**Chemistry**

A buffer solution is prepared by mixing 50.0 mL of 0.300 M NH3 with 50 mL of 0.300 NH4Cl. The pKb of NH3 is 4.74. NH3 + H2O-> NH4+ +OH- 7.50 mL of 0.125 M HCl is added to the 100 mL of the buffer solution. Calculate the concentration of NH3 and NH4Cl for the buffer solution...

*April 10, 2014 by Dee*

**algebra**

Solution A is 25% acid and Solution B is 40% acid. How much of each is needed to make 60 liters of a solution that is 30% acid?

*April 13, 2008 by hanaa*

**algebra**

Solution A is 25% acid and Solution B is 40% acid. How much of each is needed to make 60 liters of a solution that is 30% acid?

*April 13, 2008 by hanaa*

**math**

How many milliliters of a 75% acid solution must be added to 90 ml of a 10% acid solution to make a 25% acid solution?

*February 3, 2010 by Jason*

**Math**

How many milliliters of a 75% acid solution must be added to 90 ml of a 10% acid solution to make a 25% acid solution?

*February 3, 2010 by Jason*

**Math**

How much of 20% alcohol solution and 50% alcohol solution must be mixted to get 9 liters of 30% alcohol solution?

*July 27, 2011 by BoB*

**Alegebra**

Solution A is 60% alcohol and Solution B is 30% alcohol. How much of each is needed to make 30 gallons of a solution that is 40% alcohol

*May 13, 2013 by Thomas*

**algebra**

How many mL of a 60% acid solution must be mixed with a 20% acid solution to produce 200 mL of a 50% acid solution?

*September 9, 2014 by Paige*

**math**

How much of 20% alcohol solution and 50% alcohol solution must be mixted to get 9 liters of 30% alcohol solution?

*November 9, 2015 by terry*

**math 116**

How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an equation? If you replace the equal sign of an equation and put an inequality sign in its place, is there ever a time when the same value will be a ...

*March 24, 2010 by Adrian*

**math 116**

How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an equation? If you replace the equal sign of an equation and put an inequality sign in its place, is there ever a time when the same value will be a ...

*March 24, 2010 by Adrian*

**Algebra**

How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an equation? If you replace the equal sign of an equation and put an inequality sign in its place, is there ever a time when the same value will be a ...

*April 27, 2010 by Jacqueline*

**Analytical Chem**

Describe the preparation of 100 mL 0.50 M solution of Fe(NO3)3 from a stock solutiion that is 60%(w/w)Fe(NO3)3 solution with a specific gravity of 1.110 g/ml. Calculate the molar NO3 concentration in the resulting solution. Molar Mass of Fe(NO3)3: 241.86

*April 18, 2012 by BabyMikee*

**chemistry**

A student measures the conductivity of a KNO3 solution and determines it to be a strong electrolyte. the student incorrectly lists the species in solution as KNO3,K+, NO3. Give the correct list of species in solution? Please help I am lost

*November 30, 2012 by Min*

**chemistry**

what mass of ammonium chloride is dissolved in 100 grams water in each of the following solutions in 1.10 molal NH4Cl solution, in a solution which is 75% water by mass in solution with a mole fraction of 0.15 NH4Cl? please help me solve this problem. thank you!

*February 27, 2013 by andrea*

**Science**

. To make a saturated solution, 36 g of sodium chloride is dissolved in 100 g of water at 293 K. Find the percent concentration at this temperature. 3. A solution of acetone contains 20 ml of acetone in 480 ml of water. Calculate the % concentration of solution

*January 25, 2015 by Harsha*

**Chemistry**

A solution is prepared by dissolving 3.0 × 10-4 mol of AgNO3 and 3.0 × 10-5 mol of K2CrO4 in 1.00 liter of solution. With respect to Ag2CrO4 (Ksp = 1.9 × 10-12), is the resulting solution saturated, supersaturated, or unsaturated? I know you do [Ag][CrO4} but do I square ...

*November 18, 2015 by Anonymous*

**Chemistry**

If a rate of 80.0 mL of an aqueous solution of potassium hydroxide concentration of 0.25 mol / L are partially neutralized by 20.0 mL of an aqueous solution of nitric acid concentration of 0.50 mol L. Determine pH of the final solution. kOH + HNO3 -> H2O + KNO3

*January 20, 2016 by Mara*

**chem**

Consider the reaction that occurs on mixing 50.0 mL of 0.560 MNaHCO3 and 50.0 mL of 0.400 M NaOH at25oC. (a) Write a balanced net ionic equation for thereaction. (b) What is the pH of the resulting solution? (c) How much heat (in joules) is liberated by thereaction? (standard ...

*March 29, 2011 by pal*

**Math**

Two chemicals,A and B are combined in the ratio 5:11 by volume to form another solution X. A second solution Y is formed by combining chemicals, A,B and C in the ratio 2:3:15 by volume. Find the volume of chemical A in 400 litres of solution X and chemicals C in 400 litres of ...

*November 15, 2016 by Didin*

**Math**

1. Tell whether the system has one solution infinitely many solutions or no solution. 9x+8y=15 9x+8y=30 a. one solution b. infinitely many solutions*** c. no solution 2. Tell whether the system has one solution infinitely many solutions or no solution. 5x-3y=10 10x+6y=20 a. ...

*January 11, 2016 by Kaai97*

**Chemistry**

A solution is prepared by placing 72.8 g of calcium chloride in 120 g of water at 22C. The vapor pressure of water at 22C is 2.6 kPa. a)What is the boiling point of the solution? b)What is the freezing point of the solution?

*September 16, 2009 by haley*

**Chemistry**

A 1.0m solution of LiCl decreases the freezing point of water more than a .10 m solution of LiCl. Explain why based on colligative properties. I know that the 1.0m solution would decrease it more, but cannot explain why. Any help is appreciated!

*May 2, 2012 by Anonymous*

**Chemistry**

A saturated solution of Mg(OH)2 is prepared having a large excess of Mg(OH)2. Sn(NO3)2 is added to the solution. Ksp = 1.8 10-11 for Mg(OH)2 and Ksp = 5.1 10-26 for Sn(OH)2. (a) What [Sn2+] is required to start the precipitation of Sn(OH)2? (b) What [Sn2+] is required so that ...

*March 14, 2013 by Gregory*

**chemistry**

A solution of iron(III) thiocyanate was produced by dissolving 7.98 milligrams solid iron(III) thiocyanate in enough water to produce a 100.00 mL solution. What is the concentration, in molarity, of the solution?

*November 6, 2013 by Anonymous*

**ap chemistry**

Calculate the pH at the equivalence point for the titration of a solution containing 150.0 mg of ethylamine (C2H5NH2) with 0.1000 M HCl solution. The volume of the solution at the equivalence point is 250.0 mL. Kb for ethylamine is 4.7 × 10−4.

*February 4, 2014 by gabriella*

**Chemistry**

A student dissolves 22.4 g of sodium phosphate to prepare a 2.98 L solution. Another student then dilutes this solution to 4.90 L. If sodium phosphate completely dissociates, determine the number of mols of each ion in the final solution.

*December 1, 2014 by Alex*

**vapor and osmotic pressure**

A solution of the sugar mannitol ( molar mass 182.2 g/mol ) is prepared by adding 54.66 g of mannitol to 1.000 kg of water. The vapor pressure of pure liquid water is 17.54 torr at 20o C. Mannitol is nonvolatile and does not ionize in aqueous solution. a.) Assuming that ...

*October 12, 2006 by Amy*

**math**

Find conditions on k that will make the following system of equations have a unique solution. To enter your answer, first select whether k should be equal or not equal to specific values, then enter a value or a list of values separated by commas. Then give a formula in terms ...

*October 12, 2015 by Excel*

**Chemistry**

The titration of 25.0 mL of an unknown concentration H2SO4 solution requires 83.6 mL of 0.12 M LiOH solution. What is the concentration of the H2SO4 solution (in M)? A) 0.40 M B) 0.10 M C) 0.20 M D) 0.25 M E) 0.36 M The answer is supposedly C, but I got A. What am I doing ...

*December 8, 2009 by Charlie*

**Chemistry**

I have no idea what I'm doing wrong here... Question: A solution is 0.3% by mass calcium chloride. Therefore, 145 g of the solution contains how many grams of calcium chloride? My solution: 145g x (0.3g / 100g) = 0.435g or 0.44g CaCl2 What am I doing wrong? Thank you!

*May 9, 2010 by Jake*

**Chemistry**

I have no idea what I'm doing wrong here... Question: A solution is 0.3% by mass calcium chloride. Therefore, 145 g of the solution contains how many grams of calcium chloride? My solution: 145g x (0.3g / 100g) = 0.435g or 0.44g CaCl2 What am I doing wrong? Thank you!

*May 9, 2010 by Jake*

**Chemistry**

10% (m/m) Sodium Hydroxide solution, NaOH(aq) is used to break down wood fibre to make paper. A) What mass of the solute is needed to make 250mL of 10% (m/m) solution? B) What mass of solvent is needed? C) What is the molar concentration of the solution?

*May 2, 2011 by Saman*

**chemistry**

Finding molarity and molality(best answer)? An aqueous solution is prepared by diluting 3.30 mL acetone,(d= 0.789g/mL) with water to a final volume of 75.0 mL. The density of the solution is 0.993 g/mL. What is the molarity, molality and mole fraction of acetone in this solution?

*October 7, 2011 by sam*

**chemistry**

ihave two solutions. in the first solution , 1.0 moles of sodium chloride is disslved to make 1.0 liters of solution . in the second one, 1.0 moles of sodium chlorine is added to 1.0 liters of water.is the molarity of each solution the same?

*February 13, 2012 by wendy*

**Math-Help**

Consider the pair of linear equations below. 4x+6y=12 2x+3y=6 Part A: What is the relationship, if any, between 12 and 6? Part B: Do the two equations have one solution, no solution, or infinitely many solution? Explain. Part C: How can you verify your answers to Part A and B ...

*April 1, 2013 by Jayson Angole*

**math**

Consider the pair of linear equations below. 4x+6y=12 2x+3y=6 Part A: What is the relationship, if any, between 12 and 6? Part B: Do the two equations have one solution, no solution, or infinitely many solution? Explain. Part C: How can you verify your answers to Part A and B ...

*April 2, 2013 by Jayson Angole*

**Chemistry**

A solution containing 22.18 mL of a .1212 M H2CO3 solution is mixed with 17.22 mL of a .1234 M Na2CO3 solution. What is the pH of the final mixture? Ka1 = 6.2x10-7 Ka2 = 4.4x10-11. If you diluted the mixture up to 100 mL, would the pH change? If it does change, what would the ...

*December 9, 2015 by Jill*

**Math-Algebra**

Meg has a solution that is 40% alcohol and another solution that is 60% alcohol. If Meg wants 12 gal of a solution that is 45% alcohol, how much of the two solutions must be mixed?

*February 4, 2014 by McKenna Louise*

**math**

A scientist is mixing a chemical solution for an experiment. The solution contains 3/8oz of chemical and 1/6 ounce saline solution. What is the rate of chemical to saline?

*December 18, 2014 by Eli*

**Algebra 2**

A chemist has a bottle of 1% acid solution and a bottle of 5% acid solution. She wants to mix the two to get 100 mL of a 4% acid solution. How much of each should she use?

*April 22, 2015 by Megan*

**Chem**

A patient receives 3.5 L of glucose solution intravenously (IV). If 100. mL of the solution contains 5.9 g of glucose (carbohydrate), how many kilocalories did the patient obtain from the glucose solution?

*September 23, 2016 by Asia Thomas*

**Chemistry**

It says prepare a theoretical titration of 25 mL of 0.1037 M formic acid (HCOOH; pKa= 3.75) solution (diluted to 100mL volume with deionized water) by 0.0964 M solution of KOH. It asks to determine the volume of KOH solution needed to reach equivalence point. But I don't even ...

*October 25, 2010 by Anonymous*

**calculus**

Please help with this question. I have a general solution to a differential equation of 18y^3/2= TOP LINE OF FRACTION is 2(x^2-6x+23)^3/2 and this is divided by 3.plus Constant .I work out constant c to be zero. Is this correct? What is the particular solution for which y=2 ...

*May 11, 2011 by Tony*

**pre-calculus**

solve the following logarithmic equation. be sure to reject any value of x that is not in the domain of the original logarithmic expression. give the exact answer. then, use the calculator to obtain a decimal appromiation, correct to two decimal places, for the solution. In x=...

*October 6, 2012 by ladybug*

**Chemistry**

10.00 mL of an unknown base solution is titrated with .100 M HCl solution. The pH versus the volume of NaOH added is shown below. There is a graoh where there are two dotted lines signifying a pH: the highest at pH 6.31 and the lower at pH 3.92. What is the pOH pf the solution...

*March 27, 2014 by Dezzi*

**Chemistry**

Suppose the osmotic pressure of blood at 37 °C is 7.65 atm and you are preparing an intravenous (IV) NaCl solution for a patient. What concentration (in M) of NaCl solution should you prepare so the resulting IV solution is isotonic with blood, if the van’t Hoff factor of ...

*May 1, 2016 by Lola*

**Chemistry**

Suppose the osmotic pressure of blood at 37 °C is 7.65 atm and you are preparing an intravenous (IV) NaCl solution for a patient. What concentration (in M) of NaCl solution should you prepare so the resulting IV solution is isotonic with blood, if the van’t Hoff factor of ...

*May 2, 2016 by Lola*

**Biology**

In a lab experiment, we experimented with 1% glucose solution and Sorenson's solution to determine pH levels and whatnot; the other part of the lab was to determine which one, if either, was a buffering solution. According to the notes my instructor gave us, a buffers are ...

*January 28, 2013 by Emily*

**Algebra**

Suppose that x liters of 40% acid solution are mixed with y liters of a 43% solution to obtain 100 L of a 41% solution. One equation in a system for solving this problem is x + y = 100. What is the other equation?

*March 5, 2013 by Jon*

**chemistry**

CH3NH2(aq)+H2O(l)=>CH3NH3+(aq)+OH-(aq) Kb=4.4 x 10^-4 Methylamine, CH3NH2, is a weak base that reacts with water according to the equation above. A student obtains a 50.0 mL sample of a methylamine solution and determines the pH of the solution to be 11.77. (a) Write the ...

*April 4, 2013 by ashdawg*

**AP Chemistry**

CH3NH2(aq)+H2O(l)=>CH3NH3+(aq)+OH-(aq) Kb=4.4 x 10^-4 Methylamine, CH3NH2, is a weak base that reacts with water according to the equation above. A student obtains a 50.0 mL sample of a methylamine solution and determines the pH of the solution to be 11.77. (a) Write the ...

*May 2, 2013 by Christina*

**math**

Describe the number of solutions for the equation. 13. 3(x – 3) = 3x one solution no solution infinitely many solutions 14. –2(y – 3) = 2y – 6 one solution no solution infinitely many solutions

*December 12, 2012 by Anonymous*

**chem**

An aspirin tablet weighing 0.475 g has been analyzed and contains 68.2 % ASA (180.16 g/mol) by mass. A student dissolved the tablet in hot NaOH and the cooled solution was diluted with DI water to the mark in a 250 mL volumetric flask. Exactly 3.00 mL of the solution was ...

*April 18, 2011 by CHEMCHEM*

**chem**

True/false 1. will addding a strong acid (HNO3) to a solution that is 0.010M in Ag(NH3)2(^+) will tend to dissociate the complex ion into Ag+ and NH4+ 2.adding a strong acid (HNO3)to a solution that is 0.010M in AgBr2(^-) will tend to dissociate the complex ion into Ag+ and Br...

*October 22, 2009 by millie*

**Chemistry**

If 125mL of a 1.10 NaCl solution is mixed with 105mL of a 0.850M CaCl2 solution but NO reaction takes place, calculate the final concentration of each of the ions in the final solution. Please reply with the steps on how to do this question so I can learn. I can't find ...

*June 14, 2012 by bri*

**Science**

A solution is prepared by dissolving 38 g of H2S04 in 220 g water. If the density of the solution is 1.96 g/ml, find its: molality molarity mole fraction of the components of the solution normality This assignment is needed tomorrow. I really don't know the answer. I tried ...

*January 26, 2014 by Drenju*

**Chemistry**

In a volumetric analysis experiment, a solution of sodium oxalate in acidic soltuion is titrated with a solution of potassium permanganate according to the following balanced chemical equation: 2KMnO4+8H2SO4+5Na2C2O4 -> 2MnSO4+8H2O+10CO2+5Na2SO4+K2SO4 What volume of .0239 M...

*February 28, 2016 by Kaley*

**CHEMISTRY**

Consider an aqueous solution prepared from 250.0 mL of water and 1.27 g of potassium bromide. Express the amount of potassium bromide in this solution in terms of (a) mass percent (b) mole fraction (c) molarity assume the density of the solution is equal to that of water, 1.00...

*December 13, 2010 by STACY*

**holy school**

H2 S + HNO3 --------> NO + H2 O + S 150 g of hydrogen sulfide are dissolved in 3500 mL of water. a. What is the molarity of the hydrogen sulfide solution? b. How many grams of sulfur can be produced from 50 mL of this solution? c. 22.4 L of nitrogen monoxide gas are ...

*March 3, 2013 by mamta*

**Chemistry**

A solution contains Cr3+ ion and Mg2+ ion. The addition of 1.00 L of 1.55M NaF solution is required to cause the complete precipitation of these ions as CrF3(s) and MgF2(s). The total mass of the precipitate is 49.9g .Find the mass of Cr3+ in the original solution.

*October 1, 2014 by Dee*

**chemistry**

You have a solution that contains 0.25g grams of oxalic acid dissolved in 100 mL of water. This solution is placed in a separating funnel, and the 100 mL of butanol is added to the solution. calculate the mass of oxalic acid in the organic solvent

*June 16, 2016 by Grace*

**Chemistry**

A solution is prepared by adding 45.0g of Na2SO4*6H2O to pure water to make 150mL of solution. What are molar concentrations of these ions in the resulting solution? Sodium Ion? Sulfate Ion? Phosphate Ion? I've determined the solution is 1.2M 45/250.16g/mol Na2SO4*6H2O = .180 ...

*March 4, 2016 by Kevin*