# 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 362
1. ## Biomass increase !

Can anyone help please, Can anyone help me to calculate the increase in biomass in each of the three groups, Field mice Ingested 107Kj m-2 y-1 and lost 105 kj m-2 y-1 in respiration & faeces Grasshoppers ingested 444 kj and lost 374.3 kj and small birds

asked by Freddo on December 30, 2006
2. ## physics EM

A 59.0 -turn, 4.10-cm-diameter coil with R = 0.530 {\Omega} surrounds a 1.70-cm-diameter solenoid. The solenoid is 21.0 cm long and has 170 turns. The 60 Hz current through the solenoid is I_sol = (.470A)*sin(2*pi*f*t). I guess f is the frequency. Find the

asked by Spencer on April 7, 2008
3. ## calculus help

find the producer's surplus at a price level of p=\$150 for the price-supply equation p=S(x)=100-0.25x is received p=200 the final answer is 5000 is this correct and can you do the steps so i can see if i did i correct You have not defined x. Is S supposed

asked by shanere on December 2, 2006
4. ## Algeabra

For the second company, express in a table the cost of the cab ride given the number of miles provided. Number of Miles 0 1 2 3 4 5 Total Cost (dollars) a. For the second company write an equation in point-slope form. b. What does the slope mean in the

asked by Moon on December 7, 2018
5. ## Math

. Vern sold his 1964 Ford Mustang for \$55,000 and wants to invest the money to earn him 5.8% interest per year. He will put some of the money into Fund A that earns 3% per year and the rest in Fund B that earns 10% per year. How much should he invest into

asked by Josh on March 4, 2019
6. ## Chemistry

I have discovered a new chemical compound with the formula A2B. If a saturated solution of A2B has a concentration of 4.35x10-4M. a) What is the concentration of B2- ions? b. What is the concentration of A1+ ions? c. What is the solubility product constant

asked by Serena on March 16, 2014
7. ## Chemistry

Kidney stones are composed of crystals of calcium oxalate, CaC2O4. The solubility of CaC2O4 is 6.7 x 10-5 g per 100 ml of solution. What is the pH of a saturated solution of calcium oxalate? (Molar masses of Ca, C and O are 40.0 g/mol, 12 g/mol, 16 g/mol

asked by Milana on July 13, 2012
8. ## chemistry

A 15.0 ml sample of an unknown HClO4 solution requires 50.3 ml if 0.101 M NaOH for complete neutralization. What was the concentration of the unknown HClO4 solution? The neutralization reaction is: HClO4(aq)+ NaOh(aq)yields H2O(l)+ NaClO4 (aq) If anyone

asked by ben16 on December 3, 2011
9. ## chemistry

A 15.0 ml sample of an unknown HClO4 solution requires 50.3 ml if 0.101 M NaOH for complete neutralization. What was the concentration of the unknown HClO4 solution? The neutralization reaction is: HClO4(aq)+ NaOh(aq)yields H2O(l)+ NaClO4 (aq) If anyone

asked by ben16 on December 3, 2011
10. ## science

A student adds 3 spoons of salt to 100 ml of water. The solution is clear with nothing on the bottom of the cup. One spoon of the salt has a mass of 5g. What is the mass of the solution? After the water evaporates what is the mass of the solid remaining in

asked by linda on September 24, 2015
11. ## 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

asked by Brandi on August 8, 2014
12. ## chemistry

A 15.0 ml sample of an unknown HClO4 solution requires 50.3 ml if 0.101 M NaOH for complete neutralization. What was the concentration of the unknown HClO4 solution? The neutralization reaction is: HClO4(aq)+ NaOh(aq)yields H2O(l)+ NaClO4 (aq) If anyone

asked by ben on December 3, 2011
13. ## Math

I can't calculate 1 as the answer given to the following problem. I keep getting 2. Can you show me where am I going wrong? The spread of rumor among 100 people can be approximated by the equation log10(x) – log10(100-x) = (0.1)t – log10(90), where x

asked by Chris on July 3, 2008
14. ## math

The equation y=1777x27,153 can be used to predict the number of gun deaths in the US x years after 2000 that is x=o corresponds with 2000 x=3 corresponds to 2003 etc Predict the number of gun deaths in 2005 and 2009 In what year will the number of gun

asked by Daniel on May 2, 2009
15. ## chem!

Calculate the heat of reaction for the incomplete combustion of 67.0g propane producing carbon monoxide gas and water vapour. how would I go about and do this question? What are you studying? Do you know how to use the thermodynamic tables (delta Ho, etc).

asked by Chem on May 14, 2007
16. ## Physics

When standing erect a person's weight is supported chiefly by the larger of the two leg bones. Assuming this bone to be a hollow cylinder of 2.5 cm internal diameter and 3.5 cm external diameter, what is the compressive stress on the bone (in each leg) in

asked by Brittnieee. on March 4, 2012
17. ## chemistry

Nitroglycerine decomposes according the the equation: 4C3H5(NO3)3 -> 12 CO2 + 10 H2O +6N2 + O2. 15.0 g of nitroglycerine is placed in a 500 ml flask at 25.0 C. The vapor pressure of water at this temperature is 23.8 mmhg. Find the total pressure in the

asked by Ben on March 15, 2010
18. ## chemistry

If 950 mL of 0.800 M aqueous Na2CO3 and 920 mL of 0.565 M aqueous HCl are reacted stoichiometrically according to the balanced equation, how many milliliters of 0.800 M aqueous Na2CO3 remain? Round your answer to 3 significant figures. Na2CO3(aq) +

asked by Judy on June 2, 2010
19. ## chem

The "proof" of an alcoholic beverage is twice the volume percent of ethanol, C2H5OH, in water. The density of ethanol is 0.789g/mL and that of water is 1.99g/mL. A bottle of 100-proof rum is left outside on a cold winter day. a) Will the rum freeze if the

asked by alicia on February 12, 2008
20. ## chemsitry

home / study / questions and answers / science / chemistry / make sure to answer both parts: 1)balance the following ... Your question has been posted. We'll notify you when a Chegg Expert has answered. Post another question. . Question Edit question make

asked by marcus on September 29, 2015
21. ## physics

Use conservation of energy to determine the angular speed of the spool shown in the figure below after the 3.00 kg bucket has fallen 4.05 m, starting from rest. The light string attached to the bucket is wrapped around the spool and does not slip as it

asked by david on April 6, 2016
22. ## chemistry

a 5.00g sample of Al pellets (specific heat=0.89J/oC*g) and a 10.00g sample of Fe pellets (specific heat=0.45J/oC*g) are heated to 100.0oC. The mixture of hot iron Al is then dropped into 92.1g of water at 21.8oC. Calculate final temp of metal and water

asked by Rebekah on November 6, 2007
23. ## Physics - Kinematics

Need some help with my homework! Question 7 a) Acceleration is the rate of change of velocity Use your definition in (a) to show that v = u + at, where v is the final velocity, u is the initial velocity and a and t are the acceleration and the time

asked by Iman on April 17, 2012
24. ## Collega Algebra

Let f(x) = (2/4^x + 2) for real numbers x. Evaluate f(1/2001) + f(2/2001) + ... + f(2000/2001).

asked by Bianca on January 22, 2015
25. ## College Algebra

Let f(x) = (2/4^x + 2) for real numbers x. Evaluate f(1/2001) + f(2/2001) + ... + f(2000/2001).

asked by Alec on January 23, 2015
26. ## Mathematics

At Harlan County Damn in Nebraska, the U.S. Bureau reports that the storage content of the reservoir decreased from 117,811 acre-feet (38.4 billon gallons of water) on Septmber 6, 2006 to 115,579 acre-feet (37.7 billion gallons of water) on October 6,

asked by Kevin on September 8, 2008
27. ## I need 2 get these prob. b4 they get 2 me on test!

A father gives his son a ride by pulling a sled across the rough snow. The father runs across the snow with a constant acceleration while pulling the sled at F = 75.0 N, at 30 deg. above the horizontal. The combined mass the sled and son is 30.0 kg. The

asked by Matt (Newton's laws) on February 20, 2007
28. ## calculus

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 580 cubic centimeters, and the pressure is 75 kPa and

asked by rg on October 10, 2010
29. ## Calculus: need clarification to where the #'s go

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 330 cubic centimeters and the pressure is 79 kPa and

asked by Alessandra on October 27, 2014
30. ## math

it cost a company 15,000 per day to operate a plant no matter how much product they produce. in addition, it cost 75 per unit produced. write an equation that represents the total cost to operate the plant each day. use the variable x to represent the

asked by emely on February 28, 2017
31. ## calc

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 430 cubic centimeters and the pressure is 89 kPa and

asked by john smit on October 29, 2014
32. ## Chemistry (Check)

Calculate the DHrxn of C6H12O6 (s) + O2 (g) --> CO2 (g) + H2O (l) with DHf. C6H12O6(s) -1260.04 O2(g) 0 CO2(g) -393.5 H2O(l) -285.840 I balanced the equation: C6H12O6 (s) + 6O2 (g) --> 6CO2 (g) + 6H2O (l) and my work: DHrxn = [12mol(-393.5+(-285.840))] -

asked by Anonymous on November 17, 2015
33. ## Math, Algebra,

Help! I can't understand or find out the answer, I tried but I keep getting lost! George rides a cab to work 3 days a week. He pays \$3.50 for the cab to pick him up. He pays an additional fee for each mile driven. In one week, George paid \$35.25. If he

asked by Anonymous on January 11, 2017
34. ## Calc

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^1.4=C where C is a constant. Suppose that at a certain instant the volume is 670 cubic centimeters and the pressure is 97 kPa and is

asked by Anonymous on July 28, 2013

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 520 cubic centimeters and the pressure is 75 kPa and

asked by Lyle on March 15, 2009
36. ## calculus

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 380 cubic centimeters and the pressure is 89 kPa and

asked by ujkk on April 1, 2010
37. ## calculus

When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV^{1.4}=C where C is a constant. Suppose that at a certain instant the volume is 340 cubic centimeters and the pressure is 87 kPa and

asked by claudia on October 22, 2009
38. ## Math - Algebra

A. Solve the following quadratic equations. Make sure to show all your work. Do not use any method (e.g. factoring, completing the square, quadratic formula, graphing) more than twice. Use the graphing method at least once. 1. 3x+2 + 11x -20 =0 2. x2 + 3x

asked by Angela Again! on January 9, 2007

2. An isotope of sodium has a half-life of 15 h. A sample of this isotope has a mass of 2 g. a.  Find the mass equation that remains after t hours. b.  Find the mass that remains after 5 hours, to the nearest hundredth. c.  How long, to the

asked by kim on July 24, 2012
40. ## trig

An object suspended from a spring is oscillating up and down. The distance from the high point to the low point is 30 cm, and the objects take 4 sec to complete 5 cycles.For the first few cycles the distance from the mean position, d(t), in cm with respect

41. ## Science, 8th.

This flask originally held some copper wire and a clear solution of nitric acid. The two substances reacted and produced a brown gas and a blue solution. This reaction cannot be reversed. Evidence of a chemical reaction is shown by... A) ice forming. B)

asked by .jimin on February 28, 2019
42. ## Math ASAP ASAP!!!!!

Earl earns a weekly salary of \$150 plus 20% of amount of his sales for the week. Last week he earned \$230. The equation below can be used to find "s" the amount of his sales in dollars last week 230=150+0.2s What was the amount of Earl's sales last week?

asked by Courtney on January 15, 2016
43. ## calculus

a) Sketch a curve whose slope is always positive and increasing. b) Sketch a curve whose slope is always positive and decreasing. c) Give equations for curves with these properties. So for a, I drew a positive slope that was concave up. And for b, I drew a

asked by Travis on September 21, 2012
44. ## Math

Sarah can type 225 words in five minutes. She then typed 135 words in three minutes. If sarah types for 24 minutes, how many words did she type? A. What is the answer? (I answered 1080) B. Explain what the constant of variation is in the problem. Write an

asked by Max on November 15, 2015
45. ## Chemistry

What is the net chemical equation of: Reaction 1: 3.3 kcal/mol+glucose+Pi --> glucose-6-phosphate+H2O Reaction 2: ATP+H2O --> ADP+Pi+7.3 kcal/mol AND Calculate the amount of energy released in the coupled reaction. energy released: ____kcal/mol

asked by HELP! on December 2, 2012
46. ## Math

the amount of simple interest earned in a savings account varies directly with the amount of money in the savings account with the amount of money in the account. A certain bank offers a 2% savings rate write a direct variation equation for the amount of

asked by M on October 15, 2014
47. ## Math

Greg rode his bicycle at a constant speed of 20 miles per hour. Plot points on the graph to represents the distances Greg rode after 1, 2, 3, and 4 hours (1 hour= 20 miles, 2 hours= 40 miles, 3 hours= 60 miles, 4 hours= 80 hours) Then write an equation to

asked by Lucifer Albernathy on April 25, 2016
48. ## Physics

A 0.26 kg rock is thrown vertically upward from the top of a cliff that is 27 m high. When it hits the ground at the base of the cliff the rock has a speed of 24 m/s. (a) Assuming that air resistance can be ignored, find the initial speed of the rock. (b)

asked by Carden on March 29, 2010
49. ## Math

In the triangle ABC, AC=2cm, AB=x cm and angle ABC=π/2 rad. 1. Given that angle BAC=ϴ rad, and that ϴ is a sufficiently small angle, show that x≈ a + bϴ^2, where a and b are constants to be determined. 2. For this part, ϴ is not assumed to be a

asked by John on December 1, 2016
50. ## Math

In the triangle ABC, AC=2cm, AB=x cm and angle ABC=π/2 rad. 1. Given that angle BAC=ϴ rad, and that ϴ is a sufficiently small angle, show that x≈ a + bϴ^2, where a and b are constants to be determined. 2. For this part, ϴ is not assumed to be a

asked by John on November 30, 2016
51. ## Math

A school planned to buy x calculators for a total cost of Ksh 16200. The supplier agreed to offer a discount of Ksh 60 per calculator. The school was the able to get three extra calculators for the same amount of money. (a) Write an expression in terms of

asked by Anonymous on October 15, 2012
52. ## Algebra

A school planned to buy x calculators for a total cost of Ksh 16200. The supplier agreed to offer a discount of Ksh 60 per calculator. The school was the able to get three extra calculators for the same amount of money. (a) Write an expression in terms of

asked by Anonymous on October 15, 2012
53. ## Math

In a downtown parking lot,there are 5 times as many cars as there are trucks. There are 12 trucks in the parking lot. Write an equation that shows the number of cars parked in the parking lot. How many cars are in the parking lot

asked by Janarian on September 15, 2015
54. ## Chemistry

Based on pressure values for each component of the reaction, what is the value of the reaction quotient, Q? Equation: C2H2 + 2 H2 -> C2H6 C2H2 has a pressure of 5.05 atm H2 has a pressure of 4.35 atm C2H6 has a pressure of 0.0225 atm

asked by Anonymous on October 27, 2009
55. ## physics

A student opens a 12.0 kg door If the door is 2.00 m in height and 1.00 m wide what is the moment of inertia of the door about its hinges. The equation for moment of inertia about the hinges is I =1/3 mr^2 should i use the the width or the height as my r i

asked by seth on April 19, 2009
56. ## math

sorry its 5t+(6 times 10 power neg.3)....and the answer should be1.08 times 10 power -2) solve thi equation ;5t(6 multiply 10 powerneg 3)=(6 multiply 10 power negative 2).am not getting the right answer;it should be 91.08 multiply 10 power negative 2)

asked by katrina on June 20, 2007
57. ## Chemistry

Based on pressure values for each component of the reaction, what is the value of the reaction quotient, Q? Equation: C2H2 + 2 H2 -> C2H6 C2H2 has a pressure of 5.05 atm H2 has a pressure of 4.35 atm C2H6 has a pressure of 0.0225 atm

asked by Anonymous on October 28, 2009
58. ## Physics

a toy car of mass 0.01 kg, gets into an elastic collision with a toy train mass 0.35 kg. if the train is at rest and the car is moving at 2 m/s initially. how fast is the train moving after the collision? Use the equation ((2*m)/(m+t))*v

asked by L on November 1, 2017
59. ## Math

Fluffy, Spot and Champ combined dog years is 91. Spot is 14 years older than Fluffy, Champ is6 years older than Fluffy. Write and equation and solve how old Fluffy is? Thanks

asked by Dan on October 16, 2008
60. ## Calculus

the curve: (x)(y^2)-(x^3)(y)=6 (dy/dx)=(3(x^2)y-(y^2))/(2xy-(x^3)) a) find all points on the curve whose x-coordinate is 1 and write an equation for the tangent line of each of these points b)find the x-coordinate of each point on the curve where the

asked by Stephanie on November 2, 2008
61. ## Finance

i have tried so hard to understand this and i am totally confused. I just don't know where to begin. Can someone please, please help me?? Given the following information, answer the following: TR=\$3Q TC= \$1,200 = \$2Q 1. what is the break-even level of

asked by Rald on April 16, 2016
62. ## help...chemistry

i am stumped on this. please help. Balance the following equation and give the value of the stoichiometric coefficient marked with a question mark. 48KNO3 + _ C12H22O11 ---> ? CO2 +_ N2 + _K2CO3 +_ H2O thanks I left the CO2 for you but it will balance.

asked by key on January 21, 2007
63. ## Math

A physics student stands at the top of a hill that has an elevation of 37 meters. He throws a rock and it goes up into the air and then falls back past him and lands on the ground below. the path of the rock can be modeled by the equation y = -0.2x^2 +

asked by Anonymous on March 27, 2018
64. ## chemistry

what is the chemical equation for citric acid + sodium hydroxide? I will be happy to critique your thinking . Remember a salt and water will be formed. is it : C6H8O7 + 3NaOH--> NaC6H5O7 + 3H2O ? I would have written citric acid in this form H3-C6H5O7, and

asked by bob on June 5, 2007
65. ## Chemistry

Please check a Nernst equation for me? Calculate the cell potential for the following reaction as written at 61 °C, given that [Zn2 ] = 0.800 M and [Fe2 ] = 0.0170 M. Half reactions: Zn-->Zn^2+ + 2e^- (potential= -0.76)(anode) Fe^2+ + 2e^- -->Fe

asked by Miaow on April 29, 2012

ln [5.01E-3] = ln(4.86E-2) - (1.80E-2s-1)(t s) Solve for t. t = 126 s First I did 4.86e-2 - 1.80e-2 and then on my calculator I pressed the 2nd button and then ln and got 1.031. Then I did the same thing to get the ln of 5.01e-3 and divided that by 1.031

asked by Hannah on March 8, 2012
67. ## algrebra 2

it is called completing the square here is the equation 4x^2-4x+1=9 if anyone can help me please do okay i really need ot understand this 4x^2-4x+1=9 Move the numbers to the other side. 4x^2 -4x = 9-1 4x^2 -4x = 8 Now factor out 4 to make things easier.

asked by lisa on November 2, 2006
68. ## Chemistry

The following equation represents the decomposition of a generic diatomic element in its standard state. (1/2)X2(g)--->X(g) Assume that the standard molar Gibbs energy of formation of X(g) is 5.45 kJ·mol–1 at 2000. K and –64.30 kJ·mol–1 at 3000. K.

asked by BOB on April 25, 2014
69. ## Physics

In a game of basketball, a forward makes a bounce pass to the center. The ball is thrown with an initial speed of 4.3 m/s at an angle of 15 degrees below the horizontal. It is released 0.80m above the floor. What horizontal distance does the ball cover

asked by Priscilla on February 22, 2012
70. ## MATH

Julia and Kevin are playing games at the arcade. Julia started with \$15, and the machine she is playing costs \$0.75 per game. Kevin started with \$13, and his machine costs \$0.50 per game. After how many games will these two kids have the same amount of

asked by TONY on January 8, 2015
71. ## Biology

Which of the following is the balanced equation for photosynthesis in plant cells? A 3C0+ 3H0 + Energy --)-CH120 + 30 2 266 2 B. 6C0+ 6Hp + Energy--)-CHp + 60 2 616 2 C. CH0 + 30--)-3C0+ 3H0 + Energy 6126 2 2 2 D. CHp + 60--)-6C0+ 6Hp + Energy 616 2 2 I

asked by Dulce on July 14, 2014

A sperm whale can stay under water 7 times as long as x minutes more than a platypus can. Write and equation that states the relationship of the minutes these two mammals can stay under water. Sperm Whale- 112 Platypus-10 My answer: 7x+10 x=112 Is my

asked by jamar on January 8, 2015
73. ## Algebra 2

Can you check my answer and the work? Thank youu~~ (2x-y)7 128x7 -448x6y -672x5y2 -560x4y3 -280x3y4 -84x2y5 -14xy6 -y7 orr 128x7 -448x6y +672x5y2 - 560x4y3 +280x3y4 -84x2y5 +14xy6 -y7 Ps: the 7 in the equation is the exponent and the numbers after the

asked by Anonymous on January 11, 2011
74. ## Fractions.. :S

How would I work out this question...? A car costs 1,150 after it was reduced by 15%. What was the original cost? :S If x is the original cost, then .85*x = 1,150 or x = 1,150/.85 So I would divide by 85 and times by 15 and then add my answer to 1,150? No,

asked by Sarah on October 18, 2006
75. ## Algebra

The equation y = 1777x + 27,152 can be used to predict the number y of gun deaths in the United States. x years after 2000, that is x=0 corresponds to 2000: x = 2 corresponds to 2002, x = 5 corresponds to 2005, and so on. Preddict the number of gun deaths

asked by Jackie on August 18, 2010
76. ## Math

Suppose you have a lemonade stand, and when you charge \$1 per cup of lemonade you sell 50 cupes. But when you raise your price to \$2 you only sell 25 cups. Write an equation for the nuber of cups you sell as a function of the price you charge. Denote "C"

asked by Stephanie on January 19, 2009
77. ## Math

Write an algebraic equation for each of the following sentences. _____________ 12) One-third of a number is thirty-five. _____________ 14) Two times the sum of a number and five is twenty six. _____________ 16) The quotient of a number and two increased by

asked by Barry Vacker on January 24, 2019
78. ## Pre Calc

I already asked this question and had some help, but I am still confused on a piece of it. I'm not sure what differentiate is. I understand how you got a and b, but I am confused with c. What is differentiate and how did you get the equation dA/dx = 72 -

asked by MUFFY on October 5, 2009
79. ## Physics

An object is placed 20.0 cm from a thin converging lens along the axis of the lens. If a real image forms behind the lens at a distance of 8.00 cm from the lens, what is the focal length of the lens?

asked by Lauryn on February 2, 2017
80. ## math

to which subsets of real numbers does the number -22 belong? choose all that apply a) whole numbers b) rational numbers c) integers d) irrational numbers e) natural numbers

asked by art on September 20, 2016
81. ## Chemistry

I have know clue how to answer this, but I tried something.(predicting products of electrolysis in aqueous solution)/ Predict the products of the electrolysis of a solution of aqueous MnSO4. I first wrote this: Mn^2+ SO4^2- Then for Mn^2+, it can be

asked by Sara on June 16, 2015
82. ## Chemistry

Calculate the molarity of a solution made by adding 33.4 mL of concentrated nitric acid (70.4 % by mass, density 1.42 g/mL) to some water in a volumetric flask, then adding water to the mark to make exactly 2000 mL of solution. (It is important to add

asked by JO on June 23, 2015
83. ## Chemistry

The boiling point of an aqueous solution is 102.16 C. What is the freezing point? Dr. Bob, If you happen to answer this question, I was the one that a question earlier about how to know what Kf constant to use [water vs benzene?] and i didn't notice that

asked by Tracy on February 17, 2012
84. ## Chemistry

Calculate the concentration of bromocresol green (BG) indicator It says that Molar absorptivity = Absorbance at a wavelength/ concentration of BG indicator I am having trouble calculating the concentration of BG. Other info: Stock solution of BG = 80.0

asked by Catherine on April 25, 2013
85. ## Chemistry

Lactic acid is a major component of Ringer’s solution, which is used as an intravenous fluid to maintain fluid balance in trauma patients. The pH of a 0.100 M lactic acid solution is around 2.44. Based on this information, determine the value of the acid

asked by Anonymous on October 26, 2017
86. ## Chemistry

A buffer contains 5.00 M acetic acid and 5.00 M acetate anion. Gaseous HCl (0.010 mole) is added to 1.00 L of this buffer solution (the total volume does not change). For this buffer solution, the initial pH is_______and the final pH after the addition of

asked by Ivana on May 2, 2010
87. ## chemistry

calculate the mass of NaOH neded to prepare 500mL of a 0.10 M solution. I'm pretty sure the answer is 2g, but how do I get to that? Another question: calculate the molar amount of KHP used to neutralize the NaOH solution. .51 g of KHP was added to 50 mL of

asked by Rebecca on October 14, 2007
88. ## Chemistry

silver ions in a solution of silver salts can be recovered by immersing copper metal in the solution. crystals of pure silver are deposited on the silver metal. design an experiment to determine the number of moles of silver atoms that form describe the

asked by stacy on August 11, 2010
89. ## Chemistry

silver ions in a solution of silver salts can be recovered by immersing copper metal in the solution. crystals of pure silver are deposited on the silver metal. design an experiment to determine the number of moles of silver atoms that form describe the

asked by stacy on August 11, 2010
90. ## chemistry

A 250.0 mL sample of an aqueous solution at 25 degrees Celsius contains 35.8 mg of an unknown nonelectrolyte compound. If the solution has an osmotic pressure of 11.25 mmHg, what is the molar mass of the unknown compound? a.) 237 g/mol b.) 484 g/mol c.)

asked by Bru on October 2, 2012
91. ## Chemistry

silver ions in a solution of silver salts can be recovered by immersing copper metal in the solution. crystals of pure silver are deposited on the silver metal. design an experiment to determine the number of moles of silver atoms that form describe the

asked by annonomus on August 11, 2010
92. ## math

Could someone check these questions for me? Please? My answers are under the questions... Questions~ 1. Solve: | x | = 6 |6|=6 and |-6|=6 x must be 6 or -6 2. Solve: | x + 7 | = 12 (x+7)=12 and -(x+7)=12 x+7=12 and -x-7=12 x= 5 and -19=x The the solution

asked by Abby on October 2, 2015
93. ## 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

asked by Lauren on February 7, 2008
94. ## geography

teh type of erosion mainly found on the upper course of rivers are: a.hydralic action,lateral and abrasion b.hydralic action and solution c.abrasion and solution d.hydralic action and attrition

95. ## chemistry

The weight of a china dish with a saturated solution of sodium nitrate at 40°C is 80 g. After evaporating the whole solution the dish's weight along with the crystals is 40 g and solubility of NaNO3 at 40°C is 20 g. What is the weight of empty china dish

asked by Anonymous on October 5, 2016
96. ## chemistry

Both Fe2+ and Cd2+ are precipitated by sulfide. However, they can be quantitatively separated through pH adjustment. You are given a solution containing 0.086 M Fe2+ and 0.062 M Cd2+. Calculate the [H+] range for a saturated H2S solution (ie, [H2S]=0.10 M)

asked by Tanner on March 25, 2012
97. ## Chemistry

Help with lab report Need Help finishing my lab report.KNOWN VALUES ARE V OF HCL=50ML,M=2.188.V OF NAOH=55.3ML,M=2.088.INTIAL TEMP FOR HCL=22.5C,NAOH IS 23C.this is for part A: Mass of final NACL solution assuming that the density of a 1 M Nacl solution is

asked by randy on October 26, 2012
98. ## Physics

Mission Impossible: Special agent Ethan Hunt tries to escape an assassin by jumping horizontally off a flat roof. His goal is to reach a window, two stories or 5.15 m down, on the building across the alley. Ignore air resistance. If the alley is 11.9 m

asked by Anonymous on February 18, 2014
99. ## Calculus

When air expands adiabatically (without gaining or losing heat), its pressure and volume are related by the equation where is a constant. Suppose that at a certain instant the volume is cubic centimeters and the pressure is kPa and is decreasing at a rate

asked by Jason on October 26, 2010
100. ## Algebra

Jesse Played two days of golf. On the second day, he got a score of six bellow par, or -6. His total score for the two days was o above par, or 0. Define a variable. Then write and solve an equation to find the score Jesse got on the first day. Show your

asked by Ella on November 8, 2017