1. chemistry - exam practice help!!

    Given the table below predict the numerical value of the standard cell potential for the reaction: 2 Cr(s) + 3 Cu2+(aq) 2 Cr3+(aq) + 3 Cu(s) Half Reaction E (volts) (1) Cr3+ + 3 e- Cr E= -0.74 (2) Cr3+ + e- Cr2+ E=-0.41 (3) Cr2O72- + 14 H+ + 6 e- 2 Cr3+ +

    asked by Anya on December 13, 2012
  2. Chemistry

    In a lab that I am doing I am having difficulty in determining this: What are two indications that suggest a reaction has taken place when HCI was added to Mg? In this lab I am taking 0.1 Mg and adding it to the flask, then recording the temperature of the

    asked by Anonomyous on February 14, 2009
  3. college

    A standard voltaic cell is constructed so that the overall cell reaction is 2Al+3(aq) + 3M(s) --> 3M+2(aq) + 2Al(s) where M is an unknown metal. If ∆G⁰= -411 kJ for the overall cell reaction, identify the metal used to construct the standard cell.

    asked by Stephanie on April 28, 2010
  4. chemistry check my work

    the equilibrium-constant expression for a reaction is kc= [N2][H2O]2 ---------- [NO]2[H2] what is the equilibrium-constant expression when the equation for this reaction is halved and then reversed? 2NO + 2H2 --> N2 + 2H2O NO + H2 ---> N + H2O N + H2O -->

    asked by Anna on April 14, 2010
  5. CHEMISTRY

    Identify the conjugate base in the following reaction. H2O (l) + HCO31- (aq) ¨ H3O+ (aq) + CO32- (aq)? Identify the Bronsted-Lowry acid in the following reaction. H2O (l) + HCO31- (aq) ¨ H3O+ (aq) + CO32- (aq)

    asked by AL on December 3, 2014
  6. chemistry

    Calculate the change in entropy (ΔS˚) of reaction (J/K) for the equation as written. BaCO3(s) → BaO(s) + CO2(g) Table: S° (J/(K mol)) BaCO3(s) = 112 BaO(s) = 70.3 CO2(g) = 213.7 So the answer is -41.7 I thought to find the entropy of reaction you

    asked by Carter on February 23, 2013
  7. chemistry

    For the first-order reaction A => 3 B + C, when [ A]0 = 0.014 mol·L-1, the concentration of B increases to 0.017 mol·L-1 in 2.7 min. (a) What is the rate constant for the reaction expressed as the rate of loss of A? I found this to be .1923, which I know

    asked by Val on March 31, 2010
  8. Math 2

    You should make two selections from the list below. Which two of the four equations represents parallel lines? 2x - 3y = -10 6x - 9y = 15 3x + 2y = 10 9x + 6y = 30 i think it's the second one Parallel lines have the same slope. Rework your equations to be

    asked by Francheska on November 7, 2006
  9. physics

    A passenger train is traveling at 30 m/s when the engineer sees a freight train 357 m ahead of his train traveling in the same direction on the same track. The freight train is moving at a speed of 5.9 m/s. (a) If the reaction time of the engineer is 0.43

    asked by laura on August 18, 2011
  10. AP Physics

    A passenger train is traveling at 27 m/s when the engineer sees a freight train 345 m ahead of his train traveling in the same direction on the same track. The freight train is moving at a speed of 5.9 m/s. (a) If the reaction time of the engineer is 0.36

    asked by Nick on August 15, 2015
  11. math,help

    i am having difficulty with this problem can someone help me. Problem #1 Write in simplest form (48a^5b)/(12ab^2) this is what i get: 4a^4b^-1 Problem #2 how do i start it: subtract. Express your result in simplest form (12)/(z) minus (10)/(z) Your #1 is

    asked by jasort20 on March 16, 2007
  12. chemistry

    36 colored paper clips (12 each of 3 different colors) 1.Each paper clip represents a single atom. Designate a different color of paper clip to represent atoms of oxygen (O), hydrogen (H), and carbon (C). Makes two molecules each of hydrogen (H2) and

    asked by kayla on August 1, 2008
  13. Chemistry

    In the reaction PCl3 + Cl2 ---> PCl5. If the rate doesn't increase when the concentration of PCl3 is doubled and the rate increases by a factor of four when the concentration of Cl2 is doubled, how would I write the rate law for the reaction?

    asked by Raj on February 27, 2008
  14. Chemistry

    The acid-base reaction between phosphoric acid, H3PO4, and calcium hydroxide, Ca(OH)2, yields water and calcium phosphate. For each mole of calcium phosphate produced by this reaction, how many moles of water are also produced?

    asked by Anonymous on September 19, 2009
  15. chemistry

    A mixture consisting of 1 mol of H2O (g) and 1 mol CO (g) is placed in a 11 L reaction vessel at 800 K. At equilibrium 0.647 mol CO2 (g) is present as a result of the reaction: CO(g) + H2O (g) --> CO2(g) + H2 What is K(equilibrium constant) at 800 K?

    asked by Anonymous on January 5, 2012
  16. Chemistry

    The following data were obtained at 25° C for the reaction C2H5Br + OH- ->C2H5OH + Br- Determine the rate law for the reaction from these data. [C2H5Br] [OH-] Rate 0.150 0.200 4.8 x 10-5 0.300 0.200 9.6 x 10-5 0.450 0.200 14.4 x 10-5 0.300 0.600 28.8 x

    asked by Lalit on February 6, 2012
  17. Physics

    The “reaction time” of the average automobile driver is about 0.7 s. (The reaction time is the interval between the perception of a signal to stop and the application of the brakes.) If an automobile can slow down with an acceleration of 12 ft/s^2

    asked by Babygirl on August 23, 2018
  18. physics

    a typical automobile has a maximum deceleration of about 7m/s2, the typical reaction time to engage the brakes is 0.50s. A school board sets the speed limit in a school zone to meet the condition that all cars should be able to stop in a distance of 4 m.

    asked by amanda and leah on September 12, 2012
  19. AP Chemistry

    C2H2(g) + 2H2(g) --> C2H6(g) Information about the substances involved in the reaction represented above is summarized in the following table: C2H2(g) 226.7 kj/mol C2H6(g) -84.7 kj/mol [the values are the change in enthalpy] a. write the equation for the

    asked by Anonymous on September 27, 2009
  20. chemistry

    could someone check my answers to see if they are right? Balance the following equation and give the value of the stoichiometric coefficient marked with a question mark. 6 KNO3+ _ S + ? H2O _ H2SO4+ _ N2+ _ K2SO4 answer:6KNO3 + 5S + 2H2O --> 3 K2SO4 + 3N2

    asked by key on January 24, 2007
  21. Chemistry

    The Solvay process for the manufacture of sodium carbonate begins by passing ammonia and carbon dioxide through a solution of sodium chloride to make sodium bicarbonate and ammonium chloride. The equation for this reaction is H2O + NaCl + NH3 + CO2 →

    asked by David on April 3, 2010
  22. Chemistry

    Someone said, "Calculate the total delta H of the reaction and subtract the total delta H of the product from it. If you get a positive value, it radiates heat which means it's exothermic. If it is negative, heat is needed to get a reaction so it is

    asked by A Canadian on February 11, 2013
  23. Chemistry

    Someone said, "Calculate the total delta H of the reaction and subtract the total delta H of the product from it. If you get a positive value, it radiates heat which means it's exothermic. If it is negative, heat is needed to get a reaction so it is

    asked by A Canadian on February 11, 2013
  24. Health

    A swimmer would like to improve his time in the 100 yard freestyle race. After talking to his coach, he intends to focus on one critical element at the beginning of the race. This swimmer will try to improve his 100 yard freestyle time by improving his (1

    asked by Gabby on March 24, 2014
  25. AP Chemistry

    Consider the following reaction. CaSO4(s) Ca2+(aq) + SO42-(aq) At 25°C the equilibrium constant is Kc = 2.4 10-5 for this reaction. (a) If excess CaSO4(s) is mixed with water at 25°C to produce a saturated solution of CaSO4, what are the equilibrium

    asked by Olivia on October 20, 2012
  26. chemistry

    Write the net ionic equation for any precipitation reaction that occurs when .1M solutions of the following are mixed. Does the molarity affect the equation at all, or is it just a normal net ionic equation? If the solutions are too dilute A might not ppt

    asked by Chris on October 18, 2006
  27. water vapor

    When the weather is hot, and the inside of the house is cold, why do droplets of water form on the windows? Do they form on the outside or inside of the windows? Thanks. Water droplets form because of condensation. Here is a site that that talks about

    asked by Isabella on April 23, 2007
  28. chemistry

    nitrogen and hydrogen react to form ammonia. N2+3H2=2NH3. 12 dm3 of hydrogen reacted with excess nitrogen to form 2 dm3 of ammonia. what is the percentage yield of ammonia at room temperature and pressure

    asked by haya on November 15, 2016
  29. algebra

    A wire is 264 ft in length is to be cut into two pieces, one to form a rectangle whose length is four less than twice the width, and the other to form a square whose side is equal to the sum of the width and the length of the rectangle. how long is the

    asked by Kevin on November 29, 2015
  30. Math

    Perform the indicated operations and write in standard form. Sq root of -25(3- sq root of -81) Sorry, I don't know how to do the square root symbol. I keep getting 15i-45i^2, which would be 45+15i in standard form, right? But my teacher says it's wrong, so

    asked by Chelsea on February 1, 2012
  31. Algebra

    Write the equation of the line passing through the given point with the indicated slope. Give your results in slope-intercept form. Point: (0,5) Slope:m=3/5. Show work Well, youknow the form is y= mx+b you are given m. You are given a point (0,5) Put that

    asked by Linda on May 20, 2007
  32. math

    given the equation -3x +2y =4, Write another equation that will form a linear system with: one solution, no solution and infinite solution. infinite solution: (-3x +2y =) * 3 -> -9x +6y =12 y=3/2x+4 -9x +6y =12 I think we have to multiple the first

    asked by Jay on April 16, 2015
  33. AP Chemistry

    in a coffee-cup calorimeter, 50.0 mL of 0.100 M AgNO3 and 50.0 mL of 0.100 M of HCl are mixed to yield the following reaction: Ag+ (aq) + Cl- (aq) >> AgCl (s) the two solutions were initially at 22.60 degree celsius, and the final temperature is 23.40

    asked by Kailah on October 28, 2013
  34. AP Chemistry

    in a coffee-cup calorimeter, 50.0 mL of 0.100 M AgNO3 and 50.0 mL of 0.100 M of HCl are mixed to yield the following reaction: Ag+ (aq) + Cl- (aq) >> AgCl (s) the two solutions were initially at 22.60 degree celsius, and the final temperature is 23.40

    asked by Kailah on October 28, 2013
  35. math help & correction

    Problem #1 Is this correct or wrong? Find the slope of the line passing through the points(-1, -1)and(-1, 2). Write the equation of the line. For this one I KEEP GETTING Y= - (3)/(2)x-2.5 Problem #2 Find the y-intecept and slope of 7x+9y=72 My answer:

    asked by jacky on March 31, 2007
  36. American gov

    16. What ruling did the Supreme Court make regarding flag burning in Texas v. Johnson? (1 point) It is legal to burn flags other than the U.S. flag, but burning an American flag is not free speech because it affects public morale. Burning any sort of flag

    asked by Anonymous on March 29, 2017
  37. Chemistry

    I need help finding reactions beneficial to society. Here's the assignment quoted. "Your assignment is to research two different chemical reactions that are used to address social/environmental needs or problems. These reactions must clearly be attempting

    asked by Crazy on April 10, 2010
  38. Chemistry

    I need help finding reactions beneficial to society. Here's the assignment quoted. "Your assignment is to research two different chemical reactions that are used to address social/environmental needs or problems. These reactions must clearly be attempting

    asked by Crazy on April 10, 2010
  39. chemistry

    Urbium (Ur) is an upscale element found in big cities. Its oxide (UrO2) is not very stable and decomposes readily at temperatures exceeding 66∘ C. The figure below shows how the rate of reaction varies with the concentration of UrO2 at 75∘ C. The rate

    asked by lisa on December 1, 2012
  40. Chemistry

    Calculate the concentrations of S2O8 2-, I-, S2O32 2- in moles per litre of reaction mixture given the following: 20mL of 0.1 M (NH4)2S2O8 added to: 20mL of 0.2M KI 10mL of 0.01M Na2S2O3 5mL 0.2% starch Also, calculate -(delta)S2O8 2- that is, how much

    asked by Rachel on January 24, 2011
  41. CHEMISTRY

    Urbium (Ur) is an upscale element found in big cities. Its oxide (UrO2) is not very stable and decomposes readily at temperatures exceeding 66∘ C. The figure below shows how the rate of reaction varies with the concentration of UrO2 at 75∘ C. The rate

    asked by OLEG on November 29, 2012
  42. Chemistry

    Cu(s) | Cu2+(0.10M) || H+ (0.20M), MnO4-(0.35M), Mn2+(0.15M) | C(s) Determine the cell potential. ii. Is this reaction spontaneous? Prove using ∆G. iii. The equilibrium constant can also be found from Standard Cell Potentials. Eventually the cell will

    asked by help on May 23, 2018
  43. math

    1. Is this student's work correct? ( 9 x 10^3 ) ( 5 x 10^2 ) = ( 9 x 5 ) ( 10^3 x 10^2 ) = 45 x 10^3+2 = 45 x 10^5 A. Yes. The student rewrote the problem and then multiplied correctly. *** B. No. The student should have changed the scientific notation to

    asked by check my answers please!! on September 25, 2018
  44. adjective

    Biking is a cheap form of transportation, but walking might be safer. Driving is usually the fastest method of getting around. However, careless drivers with their distracting cell phones make the roads dangerous for everyone 1. In the above passage An

    asked by Jim Collum on June 12, 2013
  45. Spanish

    I have two questions about translation. If asked this question, how do I answer it. Cual es tu numero de telefono? I know it is asking my phone number which is 447-7161 but I don't know how to put it in sentence form. The next question is Que te gusta

    asked by Megan on October 13, 2010
  46. Chemistry

    The experiment that I did in lab consisted of performing a qualitative analysis of group 1 and 2 cations and anions. The first thing that I did was to add 5 drops of 3M HCl, centrifuge it, and to observe whether a precipitate would form. It did and in the

    asked by David on April 12, 2009
  47. chemistry 20 MC questions

    1- The equipment needed to carry out a titration is: A) hot plate, pipet, and filter paper B) heat source, test tube, and filter paper C) heat source, pipet, and burette D) erlenmeyer flask, pipet, and burette 2- A student correctly predicted that 10.0 g

    asked by memo on October 22, 2012
  48. Chemistry

    The specific heat of a solution is X J/g*degreesC and its density is Y g/mL. The solution was formed by combining Z mL of solution A with Z mL of solution B, with each solution initially at J degreesC. The final temperature of the combined solutions is D.

    asked by Fred on April 2, 2010
  49. chem help

    The reaction of methane and oxygen yields carbon dioxide gas and water. The unbalanced reaction is as follows: CH4(g) + O2(g)CO2(g) + H2O(g) A. If 1.26 grams of methane are reacted, how many grams of water vapor are produced? B. If 2.796 grams CO2 are

    asked by eve on April 13, 2009
  50. chemistry

    for the chemical reaction A+B= C+D, the following experimental data were taken to determine the ratelaw equation at 300K. determine the rate law for the chemical reaction. fromthe experiment data i found out the exponetial value... but 300k part confuses

    asked by priya on July 18, 2011
  51. chemistry

    Hydrogen peroxide can be produced in the lab by reacting barium peroxide with hydrochloric acid. another product of the reaction is barium chloride. 1). what is the balanced chemical equation for the reaction? 2). what mass of hydrogen peroxide should

    asked by akboyer31 on April 22, 2012
  52. Chemistry

    The reaction Co(H2O)6^+2 + 4Cl- CoCl^-2 + 6H2O is at equilibrium. The left side is pink and the right side is blue. 1. What would happen if you added AgNO3? Would nothing happen? Or would the Ag+ react with the Cl- and shift the reaction left? 2. What

    asked by Heather on March 18, 2010
  53. Chemistry

    The reaction Co(H2O)6^+2 + 4Cl- CoCl^-2 + 6H2O is at equilibrium. The right side is pink and the left side is blue. 1. What would happen if you added AgNO3? Would nothing happen? Or would the Ag+ react with the Cl- and shift the reaction left? 2. What

    asked by Heather on March 18, 2010
  54. Chemistry

    This has to do with the reactivity series for metals (K,Na,Ca,Mg,Al,Zn,Fe,Pb,Cu,Au,Ag) Which metal is most likely to undergo the conversion M(s)->M(n+)(aq)+ne- What type of reaction is this?-oxidation ? Which metal ion is most likely to undergo the

    asked by Anonymous on March 5, 2008
  55. Chemistry

    For the reaction: V2O5 + 6HCl --> 2VOCl3 + 3H2O If 13.65g of VOCl3 was produced in this reaction, how many grams of V2O5 were reacted in excess HCl? I used stoichiometry and converted 13.65g of VOCl3 into grams of V2O5. I got 73.28 g. However, I feel like

    asked by Toby on July 24, 2011
  56. Chemistry

    Help please!!! Complete the two reduction half reactions for the cell shown at the right, and show the line notation for the cell by dragging labels to the correct position. (The electrode on the left is the anode, and the one on the right is the cathode.)

    asked by shanonn on May 6, 2013
  57. AP Physics

    To stop a car, you require first a certain reaction time to begin braking. Then the car slows under the constant braking deceleration. Suppose that the total distance moved by your car during these two phases is 56.7 m when its initial speed is 82.5 km/h,

    asked by Kristen on September 9, 2007
  58. Chemistry

    can you please please help me with these questions I don't know how to do any of them. I know how to calculate moles and grams and mole ratio,etc but I don't understand the limiting excess reactant and yield stuff. Thanks! 1.In the following chemical

    asked by molly on October 2, 2016
  59. Chemistry

    can you please please help me with these questions I don't know how to do any of them. I know how to calculate moles and grams and mole ratio,etc but I don't understand the limiting excess reactant and yield stuff. Thanks! 1.In the following chemical

    asked by molly on October 2, 2016
  60. University Organic Chemistry

    Lab questions to Diels Alder butadiene experiment : Why do the anhydride groups of the maleic anhydride reactant help the Diels-Alder reaction go faster? Why does the diene need to be in the s-cis conformation to give the cyclic product? Why is it not

    asked by James on January 29, 2018
  61. Chemistry

    I did a lab where we had to determine the iron content in ore...i am confused about the reactions that occured during the reaction...i need reactions for the following... 1) The samples were treated with 6M HCl until all the iron ore dissolved.Assuming all

    asked by Joanna on December 1, 2009
  62. Math

    Ok I'm on castle learning and for homework this weekend we have to do #1-4 (assignments) that is due on Saturday @ midnight because that the time it will close and I need help on this question. My assignment is: Math 7 (Q1) Assign #2 - Fractions (i already

    asked by Laruen on November 12, 2011
  63. ela

    The poems are concrete cat haiku and limerick in the poems you read in collection 3 the poets choose different forms to express their thoughts and feelings about the subject. Imagine That there poetic forms changed. How would each poem be different if its

    asked by URGENT HELP!! SO URGENT on March 8, 2017
  64. chemistry

    the reaction of methane and water is one way to prepare hydrogen for use as a fuel: methanw react with water to from carbonmonoxide and hydrogen if you begin with 995g of methane and 2510g of water, 1.which reactant is the limiting reactant? 2.what is the

    asked by dennis on February 13, 2016
  65. Chemistry

    At 25°C, K = 0.090 for the following reaction. H2O(g) + Cl2O(g) equilibrium reaction arrow 2 HOCl(g) Calculate the concentrations of all species at equilibrium for the following case. 1.3 mol pure HOCl is placed in a 1.6 L flask [HOCl]________

    asked by Ann on February 27, 2012
  66. chemistry (Organic)

    According to the two reactions below; 1-chloro-2,2-dimethylbatune + (warm NaOH 3)) 1-chloro-2-methylpropane + (cold dil.NaOH) 1) identify whether the reactions are Nucleophilic Substitutions (SN) or Elimination (E) reaction. 2) Complete the reaction

    asked by johnny on October 8, 2015
  67. Math

    A solid sphere of 1.46kg and radius 0.1m, is rolling down a rough plane that is inclined at an angle 30 degrees to the horizontal. The 3 ferces acting on the sphere are its weight, friction force and the normal reaction. The sphere starts rolling down when

    asked by Tasneem on April 27, 2013
  68. Math

    A solid sphere of 1.46kg and radius 0.1m, is rolling down a rough plane that is inclined at an angle 30 degrees to the horizontal. The 3 forces acting on the sphere are its weight, friction force and the normal reaction. The sphere starts rolling down when

    asked by Tasneem on April 27, 2013
  69. chemistry

    A 0.286g sample of Zn was used to produce H2(g)by the reaction. Zn(s)+ 2HCl(aq)> ZnCl2(aq) + H2(g) The barometric pressure was recorded as 761.6mm Hg and room temperature was 20degreesC. When the water levels of the eudiometer tube and graduated cylinder

    asked by joann on December 3, 2012
  70. Chemisty

    Fluorine gas can react with ammonia gas to produce dinitrogen tetrafluoride gas and hydrogen fluoride gas. This reaction is described by the following balanced equation: 5 F2 (g) + 2 NH3 (g) N2F4 (g) + 6 HF (g) What mass of hydrogen fluoride gas is

    asked by Anna on March 8, 2013
  71. Advanced Algebra

    I some problems that I need help with please. Add or subtact as indicated and write the results in standard form. 4. 6-(-5+7i)-(7-2i) Divide and express the result in standard form. --These problems I don't understand, do you have to multply the

    asked by Aly on August 18, 2007
  72. chemistry

    2.9 The standard enthalpy of formation of the metallocene bis(benzene)chromium was measured in a calorimeter. It was found for the reaction Cr(C6H6)2(s) → Cr(s) + 2 C6H6(g) that . Find the corresponding reaction enthalpy and estimate the standard

    asked by girlgirl on June 18, 2011
  73. CHEMISTRY> HELP QUICK! pls

    1. The rate of a chemical reaction may be defined as: a) The speed at which a molecule travels from point A to point B. b) The change in concentration of reactants or products per unit time. c) The change in concentration of reactant divided by change in

    asked by Lucinda on August 28, 2010
  74. chemistry

    Referring to the following reaction: Pb(NO3)2 (aq) + Na2SO4 (aq) -->PbSO4 (s) + 2NaNO3 (aq) A solution of 0.114 M Pb(NO3)2 with a volume 10.6 mL is added to 12.4 mL of a solution of 0.105 M Na2SO4. Calculate the number of grams of PbSO4 that will form. I

    asked by Mona on May 6, 2015
  75. Math

    The parametric equation {x=t^2+4t+8 ; y=t+4 a. Reduce the equation to simplest rectangular form b. Determine the Center and the type of graph of the resulting equation. c. Graph the equation in rectangular form

    asked by Allyssa on June 25, 2015
  76. Math

    I need help please A computer can execute 64 instructions per second. How many instructions can it execute in 10 minutes? Multiply 3 1/6 x 9/11 x 6/17. Write the answer in simplest form Divide 6/25 / 2/15. Write the result in simplest form.

    asked by Sonya on February 9, 2008
  77. precalculus

    5x+3y=8 convert each rectangular equation to polar form Convert each polar equation to rectangular form: a r=9cos0 b r=5 c rsq= cos 20 d r= 3____ 3+sin 0 Is this a test?

    asked by yvonne on May 17, 2007
  78. Chemical Reactions

    How can i get the step by step procedure for a chemical reaction? For example: the step by step procedure for the synthesis reaction of ammonia

    asked by Chemistry on April 12, 2015
  79. Chemistry

    The ionization constant Ka of an indicator HIn is 1.0x10^-6. The color of the nonionized form is red and that of the ionized form is yellow. What is the color of this indicator in a solution whose pH is 4.00? (The question mentions that you can use the

    asked by Taylor on February 26, 2014
  80. Combustion

    In a combustion reaction, do the products or the reactants store more energy? It is the products right? As heat energy goes into the products. Potential energy is greater in the reactants. Heat is lost in the reaction, so the products have lower energy.

    asked by Steve on March 2, 2007
  81. Chemistry

    Consider the following reaction: CO2 (g) + H2 (g) CO (g) + H2O (g) Calculate the value of the equilibrium constant, Kc, for the above system, if 0.1908 moles of CO2, 0.0908 moles of H2, 0.0092 moles of CO, and 0.0092 moles of H2O vapour were present in a

    asked by kevin on February 25, 2016
  82. Complex Analysis

    I need help converting the complex number z = (-1 + sqrt(1 + 4i))/2i to the form rei^(theta). I found what the number in the square root is in the form rei^(theta) is which is sqrt(1 + 4i) = sqrt(17) e^i(tan-1(4) + pi*k) , but I am having trouble dealing

    asked by Kelsey on October 21, 2017
  83. Jay

    Please help me to solve this problem. Thank you in advance for helping to solve this problem. Have a great day. Here is the question? Use the point-slope form to write the given slope and point. Leave the equation in that form: slope 7/8, passes through

    asked by Anonymous on October 20, 2014
  84. chemistry

    Fluorine gas can react with ammonia gas to produce dinitrogen tetrafluoride gas and hydrogen fluoride gas. This reaction is described by the following balanced equation: 5 F2 (g) + 2 NH3 (g) N2F4 (g) + 6 HF (g) What mass of hydrogen fluoride gas is

    asked by chelsie on June 5, 2018
  85. chemistry

    I can't figure this question out for the life of me. If anyone could help me, that'd be great! Given change of heat of formation for Cu^2+ (aq)=+71.7kJ/mol and that for Zn^2+(aq)= -153.9kJ/mole; find the heat of reaction for: Zn(s) + Cu^2+(aq) -> Zn^2+(aq)

    asked by Anonymous on June 24, 2006
  86. Chemistry

    If you mixed water and dilute sulfuric acid, rather than concentrated sulfuric acid, would the exothermic reaction be greater or less than the exothermic reaction that occurs during hydration of a concentrated sulfuric acid? If so, why?

    asked by Michelle on March 22, 2009
  87. Chemistry

    Electrochemisry. Candy Chemist wishes to determine the concentration of CrO4^2- by electrochemical means in solution, and subsequently the Ksp of Ag2CrO4. She sets up one half-cell comprised of the Ag+|Ag couple (E=+0.799V) and a second half-cell in which

    asked by KRH on April 28, 2016
  88. PLEASE HELP CHEM!

    2 HgCl2 (aq) + SnCl2 (aq) --> SnCl4 (aq) + Hg2Cl2 (s) Hg2Cl2 (aq) + SnCl2 (aq) --> 2Hg (s) + SnCl4 (aq) For each reaction, write the two half-reactions that make it up and calculate the overall reaction potential by adding the two half-reactions. Each

    asked by Betsy on April 8, 2012
  89. biology

    What are endergonic reactions? How can endergonic reactions proceed in organisms? An endergonic reaction is a chemical reaction where the reactants have a lower free energy than the products. Enderonic reactions are coupled to exergonic reactions which

    asked by Emily on February 11, 2008
  90. Chemistry

    One proposed design for a Mars rover uses a methane gas fuel cell as its power supply. The methane fuel can be made on Mars using a chemical reaction that has been known for over 100-a the Sabatier methanation reaction: C02(g) + 4H2(g) CH4(g) +2H2O(g)

    asked by Mary on November 28, 2010
  91. Chemistry

    b)Rubidium Express your answer in condensed form, in order of increasing orbital energy. c)Tellurium Express your answer in condensed form, in order of increasing orbital energy. d)Palladium Express your answer in condensed form, in order of increasing

    asked by Chironjit on November 26, 2012
  92. Pre-Calculus

    Please check my answer: I think it's correct? 1.Find polar form of (-3,2) r=sqrt of (-3)^2 + 2^2)=sqrt (13) = 3.61 tan^-1(2/-3) = 33.79 180-33.79 = 146.31degrees polar points are (sqrt13,146.31degrees) 2. Rectangular form of (3,112degrees) 3cos112= (-1.12)

    asked by Courtney on October 13, 2011
  93. chem. stuff+5

    9. The reaction 2 H2O(l)>>>O2(g) + 2 H2(g) requires 2.06 V, but the reaction 2 H2O(l) + 2 Cl –(aq)>>> H2(g) + 2 OH –(aq) + Cl2(g) requires 2.19 V. If a 1.0 mol/L solution of aqueous NaCl is electrolyzed, what voltage should be applied to get O2(g), but

    asked by hey u!! on June 17, 2006
  94. chemistry

    We did this in a lab and nothing happened, but I'm pretty sure something was supposed to happen, so my question is: What happens when you put a pellet of sodiumhydroxide on a watch glass and observe it for 5-10 minutes? If there were hudidity in the air,

    asked by Natasha on February 14, 2007
  95. Physical-Chemistry

    Protein denaturations are usually irreversible but may be reversible under a narrow range of conditions. At pH 2.0, at temperatures ranging from about 40o C to 50o C, there is an equilibrium between the active form P and the deactivated form D of the

    asked by Paul on October 18, 2006
  96. Spanish

    I was hoping that I could get some to look my essay and tell me the proper tenses of the verbs. In the first paragraph the imperfect tense of the verb and in the second paragraph the need to be preterit tense. If you could help that would be great. Cuando

    asked by Caleb on July 13, 2015
  97. Math

    a. For the first company, express in words the amount the cab company charges per ride and per mile. Charges per ride $3.00 per mile $0.50 b. Write an equation in slope-intercept, point-slope, or standard form. Explain why you chose the form you did. Don't

    asked by Coolio on November 14, 2017
  98. PRECALCULUS

    1.) determine two pairs of polar coordinates for the point (-4sqrt3, 4sqrt3)with 0degrees less than or equal to theta less than or equal to 360degrees 2.) Use DeMoivre's Theorem to find (1-i)^10. write your answer in the form a+bi. 3.) Find the cube roots

    asked by YOSHI on April 24, 2011
  99. Chemistry...Please Help

    The Chemicals are: Baking Soda- NaHC03 Calcium Chloride- CaCl2 Bromothymol Blue - (acid base indicator) _______________________________________ What is: (a) The equations for the dissolution of calcium chloride and sodium bicarbonate in water (b) Look up

    asked by Saira on January 6, 2009
  100. Chemistry

    Benzoic acid and quinine are dissolved in a solution of dichloromethane. (benzoic acid pKa = 4.2; quinine pKa = 8.5) a) Besides the normal neutral forms for benzoic acid and quinine, will there be any other chemical form(s) present in the dichloromethane

    asked by Jemma on September 5, 2013