1. 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
  2. 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
  3. 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 13, 2012
  4. 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
  5. 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
  6. 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
  7. 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 30, 2017
  8. 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 19, 2006
  9. 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 25, 2007
  10. 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
  11. 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 13, 2009
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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 9, 2017
  22. 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
  23. 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
  24. 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
  25. 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 19, 2007
  26. 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
  27. 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
  28. 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
  29. 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
  30. 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 2, 2009
  31. 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
  32. 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 19, 2010
  33. 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
  34. 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
  35. 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
  36. 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 19, 2011
  37. 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
  38. 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
  39. 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
  40. 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
  41. 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
  42. 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 3, 2016
  43. 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
  44. 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
  45. 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 18, 2007
  46. 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
  47. 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
  48. 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
  49. 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
  50. 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
  51. 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
  52. 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
  53. 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 28, 2013
  54. 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 28, 2013
  55. 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
  56. 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 4, 2012
  57. 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 9, 2013
  58. 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
  59. 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 29, 2010
  60. 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
  61. 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
  62. 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 3, 2007
  63. 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 26, 2016
  64. 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
  65. 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
  66. 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 15, 2007
  67. 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
  68. 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
  69. 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
  70. 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
  71. 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
  72. 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
  73. 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
  74. 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
  75. 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
  76. 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
  77. 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 7, 2009
  78. 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
  79. 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 18, 2006
  80. physics

    This graph in the figure (Figure 1) shows how the temperature of an initially solid sample changes as time goes by when it is placed above a flame that delivers a constant heating power (that is, a fixed amount of energy input in the form of heat each

    asked by deeyn on September 30, 2014
  81. biochemistry

    Enzyme X is a highly pigmented protein that imparts the characteristic color to certain blue-green algae. It also facilitates a reaction necessary to the survival of this species; we can follow the kinetics of this reaction by measuring the conversion of

    asked by Ama on November 2, 2012
  82. chem

    A calorimeter contains 16.0ml of water at 15.0degrees celsius. When 1.60g of X(a substance with a molar mass of 46.0g/mol) is added, it dissolves via the reaction X(s)+H20(l)->X(aq) and the temperature of the solution increases to 25.0degrees celsius.

    asked by tomi on October 8, 2008
  83. Temperature Problem

    Q: A reaction rate has a constant of 1.23 x 10-4/s at 28 degrees C and 0.235 at 79 degrees C. Determine the activation barrier for the reaction. A: My work thus far: ln(1.23 x 10-4/0.235)=(Ea/8.314)(1/301.15-1/352.15) -7.551=(Ea/8.314)(0.0048090535)

    asked by Amy on February 2, 2013
  84. Chemistry

    (a) Which of the following are requirements for anionic polymerization? 1-A double bond 2- End groups which can react by releasing a small molecule 3- A strong base to initiate the reaction 4- A strong acid to initiate the reaction 5- An

    asked by Saraa on November 26, 2013
  85. Anatomy

    I'm posting this again today hoping someone can clarify this for me- I have two question 1.In a dehydration synthesis reaction which of the following occur- a. hydrogen and oxygen are removed from the reactant b. water is added to the reactants c. water is

    asked by Aubrey on September 13, 2011
  86. Chemistry

    A calorimeter contains 30.0 mL of water at 11.0 degrees C. When 1.50 g of X (a substance with a molar mass of 65.0 g/mol) is added, it dissolves via the reaction: X (s)+H2O (l) ---> X (aq) and the temperature of the solution increases to 26.0 degrees C.

    asked by Abby on June 22, 2012
  87. chemistry

    The alcoholic fermentation of350 g/l glucose syrup ceases when the alcoholic degree of the mixture attains 16º (16ml ethanol in 100ml of the solution) Write the reaction of the fermentation reaction. Consider the fermentation of 100L of the glucose syrup.

    asked by angy on February 27, 2017
  88. Biochem

    Glycerol 3-phosphate dehydrogenase catalyzes the reversible reaction: G3P + NAD+ --> NADH + H+ + DHAP If in the cell, the concentrations of G3P, NAD+, NADH, and DHAP are 2 mM, 4 mM, 6 mM, and 8 mM respectively. Determine if the reaction spontaneous as

    asked by Mia S on December 8, 2015
  89. Science Chemistry

    LIST: SODIUM CARBONATE. CALCIUM CARBONATE. ZINC SULFATE. ZINC NITRATE. (a) State a pair of chemicals from the list above that can be used to prepare zinc carbonate by precipitation reaction involving mixing 2 aqueous solutions together. (b) Write a

    asked by Charlotte on January 8, 2017
  90. Science Chemistry

    LIST: SODIUM CARBONATE. CALCIUM CARBONATE. ZINC SULFATE. ZINC NITRATE. (a) State a pair of chemicals from the list above that can be used to prepare zinc carbonate by precipitation reaction involving mixing 2 aqueous solutions together. (b) Write a

    asked by Charlotte on January 8, 2017
  91. Chemistry

    A 28.4288 g sample of impure magnesium car- bonate was heated to complete decomposition according to the equation MgCO3(s) ! MgO(s) + CO2(g) . After the reaction was complete, the solid residue (consisting of MgO and the original impurities) had a mass of

    asked by Brett on September 21, 2012
  92. Chemistry. Percent mass...

    A 1.009 g mixture of the solid salts Na2SO4 (molar mass= 142.04) an Pb(No3)2 (molar mass= 331.20) form an aqueous solution with the precipitation of PbSO4 (molar mass= 303.26). The precipitate was filtered and dried and its was was found to be .471 g. The

    asked by Sarah on November 22, 2008
  93. Chemistry

    A student is given a 5.000g sample to analyze composed of tin metal with a small amount of a zinc impurity. The student dissolves the metal in concentrated nitric acid, allows the reaction to continue to completion, and heats the mixture to leave 6.341g of

    asked by Nicholas on September 18, 2017
  94. half-life

    1. The half-life of a first-order reaction is 9.89 minutes. How many minutes will have elapsed after 27 half-lives? My answer is 267.03. 2. The half-life of a second-order reaction is 2.508 days. How many days will have elapsed after 8 half-lives? My

    asked by Issac on February 7, 2007
  95. Calculus

    A wire 17 inches long is cut into two pieces. One piece is bent to form a square and the other is bent to form a rectangle that is twice as wide as it is high. How should the wire be cut in order to minimize the total area of the square and rectangle?

    asked by Selena on June 13, 2015
  96. French

    I am stumped on these two questions. Unscramble the following words tp make sentences. Be sure to use the correct form of avoir. 1. j'/ordinateur/un/avoir 2. de/n'/vous/avoir/pas/chaise I know what the words mean but im not quite sure of the correct form

    asked by Nicky on September 8, 2008
  97. Math

    Describe and correct the error in writing the number 81,700,000 in scientific notation. Standard form 81,700,000 product form 81.7*100,000 scientific notation 81.7*10

    asked by Anonymous on October 3, 2010
  98. Chem

    Part A : This is the first law of thermodynamics question. case 1 - the system expands and the surroundings get hotter case 2 - the system expands and the surroundgins get colder case 3 - the system contracts and the surroundings get hotter case 4 - the

    asked by AY on November 4, 2010
  99. structural formulae

    REACTION 1 IS A CARBON COMPOUND CONTAINING AN ALCOHOL FUNCTION GROUP + REACTION 2 IS A CARBON COMPOUND CONTAINING A CARBOXYLIC GROUP. IM TRYING TO UNDERSTAND THE PRODUCT FORMULAE. CAN YOU TELL ME HOW THESE TWO FUNCTION GROUPS REACT, AND THE RELEVANCY OF CH

    asked by honey on March 9, 2007
  100. chemistry

    The voltage of an electrochemical cell depends on the redox reaction occurring in the cell. Given a redox reaction below: Zn(s) + Pb2+(aq) --> Zn2+(aq) + Pb(s) Pb2+(aq) + 2 e--->Pb(s)Eº = -0.13V Zn2+(aq) + 2 e--->Zn(s)Eº = -0.76V Calculate the E.M.F

    asked by bliss on March 10, 2016