# why does the equation x^2=-9 has no real solution why does the equation x^2 = 9 has two solutions

56,329 questions, page 439
1. ## chemistry

If a solution were made by mixing equal volume of 0.1M acetic acid(HA) and 0.1M Na-acetate(A^-) what pH would it gives?

asked by kabelo on February 20, 2011
2. ## Math

I need some help with solving this problem: Find the solution set for the system of linear inequalities. x – y ≥ 3 x + 2y ≥ 6

asked by TBA on July 20, 2014
3. ## Chemistry

The pH of a solution prepared by mixing 325 mL of 0.25 M NaOH and 675 mL of 0.20 M HClO3 is 6.50. Solve for Ka.

asked by Snoop Lion on January 29, 2014
4. ## Chemistry

How much H3PO4 is needed to neutralize 1 liter of a 0.75M solution of NaOH? (in moles)

asked by Damon on July 26, 2016
5. ## Algebra

Determine which point, if any, is in the solution half-plane of the two variable inequality. 3x – 2y < 6 Select one: a. (4, 1) b. (-1, -5) c. (1, 0) d. (2, -2

asked by Mark on February 20, 2014
6. ## maths

x^4+3x-2/(x^2+1)^3(x-4)=(Ax+B)/(x^2+1)+(Cx+D)/(x^2+1)^2+(Ex+F)/(x^2+1)^3+H/(x-4)+G/(x-4)^2.find ABCDEFGH?plz solve it a partial fraction i serious need the solution urgently

asked by anthony on July 28, 2015
7. ## government secondary school

maths:x^4+3x-2/(x^2+1)^3(x-4)=(Ax+B)/(x^2+1)+(Cx+D)/(x^2+1)^2+(Ex+F)/(x^2+1)^3+G/(x-4)+H/(x-4)^2.fine the value of ABCDEFGH,it a partial fraction o plz i need the solution urgently

asked by Anonymous on July 28, 2015
8. ## chemistry

What is the molar concentration of calcium hydroxide that has 0.185g solute in 100ml solution?

asked by n/a on March 12, 2011
9. ## Calculus

write and row reduce the augmented matrix to find the general solution: 2x - z = 2 6x + 5y + 3z = 7 2x - y = 4

asked by Liz on January 26, 2014
10. ## CHEM

WHAT IS THE pH of 1.00 molar solution of NaNO3(aq)? The Ka for nitric acid is 0.0007.show all calculations

asked by Zitha on March 12, 2011
11. ## chemistry

Calculate the normal freezing point of an aqueous solution containing 30% w/w ethylene glycol. Thanks

asked by el on October 26, 2011
12. ## bio

what will happen to a red blood cell place in a solution of 99.3% water and 0.7% salt?

asked by alex on October 26, 2011
13. ## Chemistry

The solution "head" dissolves in the water and the mixing "tail" dissolves in the oil. or The mixing "head" dissolves in the water and the solution "tail" dissolves in the oil. which one is right? thank you for your time!

asked by Baby on April 17, 2008
14. ## chemistry

The bottle of hydrogen peroxide from the store says it is a 3% solution by mass. What is its molal concentration?

asked by billy bob j on April 17, 2008
15. ## science: chemistry

How many moles of NaOH must be added to 1.0 L of 2.6 M HC3H5O3 to produce a solution buffered at each pH? 1)pH= 4.28 2)pH=pKa

asked by Julie on July 23, 2015
16. ## Chemistry

Show, with equations, why the solution from which BaSO4 is precipitated cannot be allowed to be more than 0.01-0.05M in HCl.

asked by Anonymous on October 26, 2011
17. ## chemistry

What is the molar concentration of calcium hydroxide that has 0.185g solute in 100ml solution?

asked by twynna on February 13, 2011
18. ## New delhi

Find molarity of 20%aqous soluion of amino . the density of the solution is 1.4 grams/ml

asked by Tk on July 21, 2015
19. ## Chemistry

How many grams of potassium carbonate are needed to make 0.200 L of a 2.50M solution?

asked by Hannah on February 13, 2011
20. ## Chemistry

what is the osmotic pressure produced by a 1.20M glucose (CH12O6) solution at 25 degree

asked by Elsie on May 11, 2016
21. ## chemisty

calculate the molarity of a solution with .2 moles of sodim hydroxide dissolved in .5L of water

asked by Anonymous on April 27, 2011
22. ## chemistry

Now take another 35 mL of the 0.50 M pH 6.59 buffer and add 1.5 mL of 1.00 M NaOH. Using steps similar to those above, calculate the new pH of the solution. find pH

asked by Taylor on October 24, 2011
23. ## Chemistry

How much by mass of Urea (NH2)2CO is required for a 32.5% solution in one litre of water.

asked by Bill on October 24, 2011
24. ## Chemistry

In a titration of 35.00 mL of 0.737 M S, __________ mL of a 0.827 M KOH solution is required for neutralization.

asked by Charlie on October 5, 2012
25. ## Chemistry

What is the concentration of 127 mL of solution made with .450 g of nickel (II) nitrate hexahydrate?

asked by Morgan on May 22, 2016
26. ## Chemistry

what would be the molality of a solution if 71g of Cl2 were added to 400 mL of acetone (D=0.788 g/mL)

asked by Caleb on March 18, 2014
27. ## CHEMISTRY

If a nickel rod embedded in a silver nitrate solution , what do we predict ? explain

28. ## Chemistry

What mass of NaOH is required to prepare 500.0 mL of 0.1029 M stock solution?

asked by Erin on October 9, 2012
29. ## chemistry

What is the concentraton of a solution made by dissolving 0.5 moles of solute in 9.0 liters of water?

asked by Juliettte on March 5, 2011
30. ## chemistry

The concentration of Mg2+ ion in a solution is 0.010M. At what pH will Mg(OH)2 first precipitate? (Given Ksp Mg(OH)2 equals 1.2*10-11)

asked by Lisa on June 16, 2015
31. ## Chemistry lab

What mass of NaOH is required to prepare 500.0 mL of 0.1029 M stock solution?

asked by Donnie on October 9, 2012
32. ## Chemistry

What mass of the following solution contains 0.100 mol of solute? 0.334 molality NH4NO3

asked by Anonymous on April 24, 2011
33. ## chemistry

how many grams of NaCl (molecular weight 58.5) should be used to prepare 20 liters of a solution containing 154mEq/L?

asked by mary on February 27, 2011
34. ## chemistry

What is the molarity of a solution prepared by dissolving 2.41 g of potassium iodide, KI in 100 mL of water?

asked by Ambra on May 6, 2012
35. ## Chemistry

how many grams of potassium dichromate are needed to make 250 mL of a 0.75 molar solution?

asked by Bobbi on March 3, 2011
36. ## Chemistry

how many grams of potassium dichromate are needed to make 250 mL of a 0.75 molar solution?

asked by Bobbi on March 3, 2011
37. ## Chemistry

What mass of the following solution contains 0.100 mol of solute? 0.334 molality NH4NO3

asked by Anonymous on April 24, 2011

I've been stuck for a while on this problem Which ordered pair represents the solution to the system of equations? { 5x+3y=7 { 3x-5y=-23

asked by Ayden on May 26, 2016
39. ## math

use dominance to slove the game with following pay-off matrices: ((2 3 1/2) (3/2 2 0) (1/2 1 1)). ANS: A=(1/4,0,3/4); B=(1/4,0,3/4); v=7/8. i got answer, but how to do this? i need solution

asked by priya on May 29, 2016
40. ## Chemistry

A 25.0-g sample of sodium hydroxide is dissolved in 400.mL of water. What is the concentration of the solution?

asked by Mayra on May 30, 2016
41. ## Chemistry

What is the concentration of H3O+ in a solution with the following pH values. Enter your answer in scientific notation. a. 6.66 b. 13.40 c. 13.17 d. 2.39

asked by chelsey on March 18, 2014
42. ## Chemistry

What mass of NaOH is required to create 500 mL of a .4 M solution of Sodium Hydroxide(aq)?

asked by Scott on February 13, 2014
43. ## chemistry

calculate the mass of sodium hydroxide needed to prepare 100 ml of a .10 m solution

asked by mike on October 7, 2012
44. ## chemistry

calculate the mass of sodium hydroxide needed to prepare 100 ml of a .10 m solution

asked by mike on October 7, 2012
45. ## Chemistry II

What is the molal concentration of an aqueous calcium chloride solution that freezes at -2.43 degrees C?

asked by Chrystal on February 3, 2014
46. ## Chemistry

What is the molal concentration of an aqueous calcium chloride solution that freezes at -2.43 degrees C?

asked by Arya on February 3, 2014
47. ## Chemistry

In a titration of 35.00 mL of 0.737 M S, __________ mL of a 0.827 M KOH solution is required for neutralization.

asked by Charlie on October 5, 2012
48. ## math

find missing coordinate of the order repair so it is a solution 2x+4y-6=0 (2, ) my answer was (2, 1/2) or (2,2/1) but it is incorrect

asked by Felicia on July 1, 2016
49. ## chemistry

How many grams of Lead (II) Nitrate are required to make a 350mL solution of 2.5M Pb2+?-

asked by valentina on February 20, 2011
50. ## Chemistry

Calculate the pH and the pOH of an aqueous solution that is 0.025 M in HCl(aq) and 0.075 M in HBr(aq) at 25°C.

asked by Alex on October 6, 2012
51. ## chemistry

What is the pH of a solution made by adding grams of NH4Cl, to 550 mL of 0.205 M NaOH?

asked by Tom on April 20, 2011
52. ## Chemistry

What is the concentration of a solution made by diluting 95 mL of 6.0 M HCl to a final volume of 750 mL

asked by Tish on October 14, 2012
53. ## Chemistry

Calculate the pH of the solution that results from mixing 30.0 mL of 0.050 M HCN(aq) with 70.0 mL of 0.030 M NaCN.

asked by Anonymous on March 19, 2014
54. ## math

how do you write an open statement involving an absolute value inequality when all you are given is the graph of the solution?

asked by ed on September 20, 2007
55. ## science

Calculate the amount of h2so4 required for preparing 500ml of 2MH2so4 solution.

asked by v¨ªşhął on February 29, 2016
56. ## Chemistry

Calculate the mass of HF required to prepare 200 mL of 0.25 mol/L solution. P = 40%; d = 1.14 g/cm3

asked by Jacke on June 21, 2016
57. ## chemistry

what is the actual freezing temperature of a 0.50m aqueous solution of sodium chloride?

asked by kim on May 18, 2016
58. ## language arts

please help... Which of the following signal words could identify a problem-solution text structure? A.first B.i think(I PICK THIS) C.therefore

asked by taylor on February 5, 2014

please help... Which of the following signal words could identify a problem-solution text structure? A.first B.i think C.therefore(I PICK THIS)

asked by taylor on February 5, 2014
60. ## Density of a CUSO4 solution

I need to determine the density of a CUSO4 solution of 1% concentration from a 10cc pipette volume.

asked by Lorraine on March 6, 2011
61. ## Chemistry

what is the percent by mass of a solution by dissolving 200 g of NaCI in 500 mL of water?

asked by Annyssa on June 15, 2016
62. ## pre-calculus

please help me with thisone thanks solve the inequality algebraically. Express the solution in interval notation. (x-8)^2/x^2-36 > 0

asked by dave on March 1, 2011
63. ## Chemistry

The Ka values of H3PO4 are shown below. Ka1 7.5 10-3 Ka2 6.2 10-8 Ka3 4.8 10-13 What is the pH of a 0.19 M solution of NaH2PO4?

asked by Chris on March 8, 2009
64. ## chemistry

Calculate the molality of sulphuric acid solution in which mole fraction of water is .85

asked by swastika on June 3, 2014
65. ## chemistry

How many moles of Na2CO3 would be needed to react with 750 mL of 0.250 M H2SO4 solution?

asked by Emily on April 1, 2011
66. ## value

what happens when a solution of iron 2 sulphate in a test tube was bubbled through chlorine gas

asked by value on September 24, 2016
67. ## chemistry

You have prepared a saturated solution of at 20 using 31.0 of water. How much more solute can be dissolved if the temperature is increased to 30?

asked by Anonymous on March 31, 2011
68. ## science

a solution made from 35 mL of ethanol and 65 mL of water produces by what percent concentration of volume

asked by frances on September 26, 2012
69. ## Science

Whta pH of the acid-base solution when the indicator turn this green colour?

asked by ATHINI on June 23, 2014
70. ## Chemistry

Calculate the grams of solute required to make 2500mL of 90% saline solution?

asked by Morgan on May 17, 2012
71. ## Chemistry

What is the molarity of a solution prepared by dissolving 4.92 g of calicum nitrate in 250 mL of water?

asked by Ambra on May 1, 2012
72. ## AP Chemistry

Will a non-volatile solute always lower the vapor pressure of the pure solvent in solution? Why or why not?

asked by Anonymous on November 21, 2009
73. ## Chemistry: Salt of weak acids and bases

If 25 mL of 0.20M NaOH is added to 20 mL of 0.25M boric acid, what is the pH of the resultant solution?

asked by Wen on April 10, 2016
74. ## chemistry

How many grams of potassium permangate are needed to decolorized 1g of 2-pentene in basic solution

asked by john on October 4, 2011
75. ## math

If 6 is added to the numerator and denominator of the fraction 7/9,what will be the value increase or decrease ?by how much ?i need solution answer

asked by sheirra on September 17, 2016
76. ## chemistry

If you begin with 0.030 L of a 2.5M NaOH solution, what concentration will you end up with if you dilute it to 0.050?

asked by Anonymous on February 22, 2016
77. ## science

when phenolphthalein is added to ammonium hydroxide the color of the final solution is pink?

asked by kleanface on October 31, 2012
78. ## algebra ll

Show the work to solve |2x+5| -1 < 6 and describe the graph of the solution in a complete sentence.

asked by justina on August 30, 2011
79. ## science

calculate weight by volume for 0.8molal urea,density of solution is 1.14gram per ml

asked by kk on April 14, 2016
80. ## CHEMISTRY

what volume of .0250 M MgCl2 should be diluted to 250.0 mL to obtain a solution with [Cl]=.0135?

asked by Shineylou on September 27, 2011
81. ## chemistry 12

Calculate [H3O] an [OH] for a sodium hydroxide solution having a pH of 12.5. I'm having a hard time with this i'm not sure how to start it. Please help me!

asked by Sarah on October 6, 2011
82. ## chemistry

To 50 mL of this buffer, 10.0 mL 0.76 M soium hydroxide was added, what is the pH of the resulting solution after equilibrium has been re-established

asked by cel on June 15, 2014
83. ## Chemistry

What is the pH of a one liter auqueous solution to which has been added 0.2 moles of acetic acid (CH3COOH)?

asked by Chris on January 23, 2011
84. ## gpc

Calculate the molarity of a bleach solution that is 8% by mass (m/v) or 8g/100mL sodium hypochlorite.

asked by samry on March 3, 2014
85. ## Chemistry

Calculate the solubility (in grams per 1.00×10^2 mL of solution) of magnesium hydroxide in pure water.

asked by Salma on March 28, 2016
86. ## Chemistry HELP

If 150.0 mL of 1.00 M C6H12O6 are diluted to 750.0 mL, what is the molarity of the final solution? ____ M?

asked by MBH on October 3, 2011
87. ## geometry

what is the area of a circle with a circumference of 22 pi in.? expressed in pi in. squared? and what are the steps to arrive at the solution?

asked by Rachel on April 5, 2011
88. ## Math

I am solving inequalities then graphing my solution. in a problem such as -2(c-1)

asked by Christina on May 1, 2011
89. ## biology/chem

How many grams of glucose (MW = 180 g) should we dissolve in one liter of water to get 1 molar solution?

asked by nicole on January 19, 2011
90. ## Algebra 1 (Reiny or Kuai)

Can a solution of a linear inequality lie on a dashed boundary line? Explain.

asked by Anonymous on December 19, 2013
91. ## chemistry

calculate the moles of solute present in 1.25 centimeter cube of 0.5 M h3po4 solution

asked by hifsa on June 19, 2014
92. ## chemistry

what mass of (NH4)SO4 is required to prepare 500 cm3 of M/4 solution?

asked by sarah on April 4, 2011
93. ## Chemistry

How many grams of KF do you need to weigh in order to prepare 500. mL of solution with a concentration of 0.250 M?

asked by Kiley on April 29, 2008
94. ## Math

2 liters of cleaning solution is 65% ammonia. How much water must be added to dilute it to a 40% soulition?

asked by Ashley on September 29, 2016
95. ## Chemistry

if 25.0 mL of 15M nitric acid is diluted to 125 mL, what is the concentration of the new solution? i got 3M but i don't think its right

asked by Anonymous on March 4, 2014
96. ## Chemistry

I would like to have 1 mole of Cl- ions in 500ml of water, how many grams of NaCl do I weigh out for this solution?

asked by Lindsey on January 22, 2011
97. ## Chemistry

if 25.0 mL of 15M nitric acid is diluted to 125 mL, what is the concentration of the new solution? i got 3M but i don't think its right

asked by Anonymous on March 4, 2014
98. ## chemistry

Will a precipitate form when an aqueous solution of (NH4)4CO3 is mixed with Fe(NO3)3

asked by Anonymous on October 4, 2011
99. ## chemistry

Will a precipitate form when an aqueous solution of (NH4)4CO3 is mixed with Fe(NO3)3

asked by Anonymous on October 4, 2011
100. ## chemistry

The volume of 0.025M Ca(OH)2 solution which can neutralise 100ml of0.0001M H3PO4

asked by Arun on August 31, 2015