1. Biology

    To take the energy from an exergonic reaction and use it to power an endergonic reaction, a cell can: create the energy for the endergonic reaction to occur. Why is this false? I thought a exergonic reaction create energy for the endergonic reaction to

    asked by Anon on March 18, 2013
  2. Chemistry

    1) Balance this redox reaction using the oxidation-number method. Zn + O2 + HCl ® ZnCl2 + H2O 2) Balance this redox reaction using the half-reaction method. (basic solution) Zn + MnO4- ® Zn(OH)2 + MnO2

    asked by Sara on October 13, 2010
  3. chemistry

    calculate the half-life of a first- order reaction if the concentration of the reactant is 0.0396 M at 12 seconds after the reaction starts and is 0.00579 M at 47 after the reaction starts. How long does it take for the reactant concentration to decrease

    asked by saud on November 19, 2011
  4. chemistry

    calculate the half-life of a first- order reaction if the concentration of the reactant is 0.0396 M at 12 seconds after the reaction starts and is 0.00579 M at 47 after the reaction starts. How long does it take for the reactant concentration to decrease

    asked by saud on November 19, 2011
  5. Chemistry

    For a given reaction 2A + B --> C, if the concentration of A doubles then the reaction rate doubles. If the concentration of both A and B doubles then the reaction rate increases by factor of 8. What is the order of the reaction with respect to B?

    asked by Anonymous on October 2, 2010
  6. Chemistry

    A mixture containing the same number of moles of SO2 and O2 is placed in a 2L container at 900K. The initial pressure is 1.90Atm. A reaction occurs leading to the formation of SO3: 2SO3 + O2 2SO3 After equilibrium is established the TOTAL pressure drops to

    asked by TJ on May 1, 2010
  7. Chemistry

    The reaction 2NO(g) + 2H2(g) N2(g) + 2H2O(g) goes twice as fast when the concentration of H2 is doubled but four times as fast when the concentration of NO is doubled. What is the overall reaction order? I did it like this: k[NO]^m[H2]^n 2r=[H2]^n, meaning

    asked by Jim on September 23, 2015
  8. chemistry

    The reaction of the ferric ions with isocyanate ions is an exothermic reaction. In what direction would you expect the equilibrium to move if the solution temperature is raised? Would the color of the reaction intensify? Explain. What would happen if you

    asked by Anonymous on August 15, 2010
  9. chemistry

    Given: Equation #1: 4NH3(g) + 5O2(g) = 4NO(g) + 6H2O; ΔH of reaction = -1170 kJ Equation #2: 4NH3(g) + 3O2(g) = 2N2(g) + 6H2O; ΔH of reaction = -1530 kJ Then what is the ΔH of reaction for: N2(g) + O2(g) = 2NO(g)? Enter a numerical value below and be

    asked by danny on February 1, 2015
  10. Chemistry

    In an E1 reaction using cyclohexanol with phosphoric acid as a catlyst to produce Cyclohexene + water(also used potassium carbonate as drying agent) My questions are what are the possible bases in this reaction? And which is the strongest that would be

    asked by Sara on April 3, 2009
  11. chemistry

    the following reaction may be used to remove sulfur compounds from power plant smokestack emission. 2HS(g) + SO2 >>>> 3S + 2H2O ...... DELTA h = -145 KJ the value of the euilibrium constant for this reaction is 8.0*10^15 at 25 degree celsius. a). given the

    asked by klove12 on January 16, 2012
  12. Chemistry

    Can you check my calculations, please? It's for a lab we did in order to find the the enthalpy of formation of NH4Cl(s). My final answer was -299.4 kJ, while the theoretical, or actual, value is -314.4 kJ. It was the closest value out of everyone in the

    asked by a Canadian on February 20, 2013
  13. Physics

    10. A military jet flies horizontally with a velocity of 450 m/s and 20,000 m above the ground. When the jet is straight above an artillery gun a shell is fired. Assuming the shell hits the jet. a. Calculate the horizontal component of the initial velocity

    asked by Zachary Star on September 20, 2015
  14. chemistry

    Hey Guys so I have this problem with ICE tables that is extremely confusing for me so I would love some help on it! At a Certain Temperature, the equilibrium constant for the reaction of NO with Cl2 is 6250. If the initial concentration of NOCl is 1.0M and

    asked by Bri on March 8, 2014
  15. chem

    After obtaining a greenish color in an experiment what does this tellyou about the relative concentrations of H^+ and OH^- in the solution? pls help i really need a simople explanations about this.

    asked by akira 12 on December 3, 2012
  16. AP Chemistry

    Calculate the concentration of the constituentions in solutions of the following compounds in the following concentrations: (a) 0.45 M HBr, (b) 0.045 M KOH, (c) 0.0112 M CaCl2.

    asked by Phoebe on November 24, 2016
  17. AP Chemistry

    A solution is prepared by mixing 50.0 mL of 0.17 M Pb(NO3)2 with 50.0 mL of 1.6 M KCl. Calculate the concentrations of Pb2+ and Cl - at equilibrium. Ksp for PbCl2(s) is 1.6X 10-5.

    asked by Bill on December 5, 2011
  18. chemistry

    A solution is prepared by mixing 50.7 mL of 0.28 M Pb(NO3)2 with 70.8 mL of 1.0 M KCl. Calculate the concentrations of Pb2+ and Cl - at equilibrium. Ksp for PbCl2(s) is 1.6 10-5.

    asked by jeff on February 21, 2013
  19. PLEEEEEAAAASE HELP WITH DIFFERENTIAL EQ PROBLEMS!!

    1) What are the equilibrium solutions to the differential equation and determine if it is stable or unstable with the initial condition y(-4)=1: 0.1(y+2)(4-y) 2) Use Euler's method with step size=0.5 and initial condition y(0)=3 to solve the equation

    asked by Karen on December 8, 2014
  20. Biology

    Which of the following would differ if you compared the sam reaction taking place with and without an enzyme? a. the chemical energy of the reactants**** b. the chemical energy of the products c. the energy required to start the reaction d. the overall

    asked by Anonymous on August 20, 2018
  21. Chemistry

    For a particular reaction, ΔH° is 20.1 kJ/mol and ΔS° is 45.9 J/(mol·K). Assuming these values change very little with temperature, over what temperature range is the reaction spontaneous in the forward direction? The reaction is spontaneous for

    asked by Anonymous on December 2, 2012
  22. chemistry

    For combustion of 10 grams of C4H10 excess of O2, You are obtained 25 grams of CO2 according to the reaction (to balance): C4H10+ O2→ CO2+ H2O Calculate the reaction yield of the reaction. please,could anyone help me to solve this problem.

    asked by Anonymous on July 11, 2016
  23. Chemistry

    The gas phase decomposition of dinitrogen pentoxide at 335 K N2O5(g) 2 NO2(g) + ½ O2(g) is first order in N2O5. During one experiment it was found that when the initial concentration of N2O5 was 0.218 M, the concentration of N2O5 dropped to 2.96E-2 M

    asked by Breauna on January 25, 2014
  24. chemistry

    how do you solve this problem? consider the reaction A->B the rate of the reaction is 1.6 x 10^-2 M/s when the concentration of A is 0.35 M. Calculate the rate constant if the reaction is a) first order in A and b) second order in A.

    asked by Jin on July 15, 2010
  25. chemistry

    why would lowering the temp and decreasing the pressure not increase the rate of the reaction: carbon monoxide gas is combusted in the presence of oxygen gas into carbon dioxide. (DeltaH for this reaction is -285kJ.) CO + O2 ==> CO2 + heat decreasing P

    asked by alexa on April 29, 2007
  26. Physics

    Consider the motion of a projectile. It isfired at t = 0. Its initial speed is 36 m/s and its initial projection angle is 55◦ from the horizontal. The acceleration of gravity is 9.8 m/s2 . y x What is the maximum height, h, of its tra jectory? Answer in

    asked by Bobby on December 10, 2010
  27. physics

    A little red wagon with mass 8.00 moves in a straight line on a frictionless horizontal surface. It has an initial speed of 3.80 and then is pushed 4.7 in the direction of the initial velocity by a force with a magnitude of 10.0 .

    asked by Anonymous on April 11, 2013
  28. chemistry

    A student performed two side-by-side reactions to test the decomposition of N2O5. The only difference between the two reactions was reactant concentration — reaction 1 started with 2 M N2O5 and reaction 2 started with 1.2 M. Which of the following

    asked by stop-cheating-on-apex on March 18, 2018
  29. Chemistry

    Sodium azide (NaN3) yields N2 gas when heated to 300 degrees Celsius , a reaction used in automobile airbags. If 1.00 mol of N2 has a volume of 47.0 liters under the reaction conditions , how many liters of gas can be formed by heating 35g of NaN3? The

    asked by K on March 3, 2013
  30. science - chemistry pH problems

    Here is the hint I received on how to solve those tough pH problems I posted earlier: Both of these can be solved using the H-H and doing the algebra. The math itself is hard to type out, but in Q1 the values of [NaA] and [HA] are 0.04805 and 0.15195. In

    asked by ajones51 on October 11, 2006
  31. Trigonometry

    a. Write a formula for Q as a function of t. b. What is the value of Q when t=10 1. Initial amount 2000; increasing by 5% per year 2. Initial amount 112.8; decreasing by 23.4% per year 3. Initial amount 5; increasing by 100% per year

    asked by Alex on January 16, 2013
  32. PHYSICS

    Particles 1 and 2, each of mass m, are attached to the ends of a rigid massless rod of length L1 + L2, with L1 = 19 cm and L2 = 75 cm. The rod is held horizontally on the fulcrum and then released. What is the magnitude of the initial acceleration of

    asked by Calvin on March 24, 2007
  33. CHEM

    I posted a question earlier, and i'm still abit confused. What is the reaction between potassium and aqueous sodium chloride? I was told that the products are KOH, H2, and KCl. But shouldn't the reaction be a displacement reaction? Since Potassium is more

    asked by Marrion on October 21, 2009
  34. Physics

    A coin is tossed into the air with an initial speed of 8.00 m/s. In the absence of air resistance, how high does the coin go above its point of release It rises a distance h such that the potential energy gain (m g h) equals the initial kinetic energy loss

    asked by Anonymous on January 5, 2007
  35. chemistry

    In a zero order reaction ,20% of the reaction complete in 10s .How much time it will take to complete 50% of the reaction?

    asked by tanya on May 27, 2015
  36. chemistry

    what can we say about the EA for an exothermic reaction? a...must be

    asked by Anonymous on December 1, 2010
  37. Chemistry

    What would likely happen if you were to touch a metallic beaker in which an endothermic reaction were occurring? The beaker would probably feel cooler than before the reaction started. The beaker would probably feel warmer than before the reaction

    asked by Ben on May 16, 2016
  38. AP Chemistry

    iN A LAB, the orders of two reactants, A and B, were determined experimnetally to be 2 and 3 respectively. a. write the rate law for this reaction. c. what would happen to the rate of the reaction if A were Doubled? d. what would happen to the rate of the

    asked by Sara on February 25, 2015
  39. chemistry

    Given the following reaction: 4 KO2 + 2 H2O + 4 CO2 4 KHCO3 + 3 O2 How many moles of H2O are needed to react with 12.15 moles of CO2? moles A chemical reaction occurs between solutions of LiCl and silver nitrate. This reaction produces a precipitate that

    asked by Erika on October 22, 2010
  40. chemistry

    The pollutant NO is formed in diesel engines. The reaction fixes atmospheric nitrogen with oxygen to form NO. The reaction is: N2(g) + O2(g) = 2NO(g). If the equilibrium constant for this reaction at elevated temperatures is 5.60E-11, then what is the

    asked by danny on February 25, 2015
  41. chemistry ASAP please!!

    The reaction of CO(g) + NO(g) is second-order in NO2 and zero-order in CO at temperatures less than 500K. (a) Write the rate law for the reaction. (b) How will the reaction rate change if the NO2 concentration is halved? (c) How will the reaction rate

    asked by Maria on March 15, 2011
  42. Chemistry check

    Can someone check to make sure my answer is correct? The question is: Which of the following statements is incorrect? a. Complete combustion has occured when all the carbon in the product is in the form of carbon dioxide. b. A single reactant is the

    asked by Mike on March 18, 2009
  43. AP Chem

    At a particular temperature, Kp = 0.25 for the following reaction. N2O4(g) 2 NO2(g) (a) A flask containing only N2O4 at an initial pressure of 5.3 atm is allowed to reach equilibrium. Calculate the equilibrium partial pressures of the gases. (b) A flask

    asked by Bill on January 8, 2012
  44. Chemistry

    0.5g of MG ribbon is reacted with 100ml of 1M HCL. The initial temperature of HCL is 20.4 degrees celsius. After the reaction the highest recorded temperature is 40.7 degrees celsius. Calculate the molar enthalpy of MG. I tried to find mol from HCl and

    asked by Jacob on October 17, 2016
  45. physics

    A pumpkin with a mass of 3.0 kg is launched from a catapult at an initial height of 3.5 m off the ground, with an initial speed of 16.2 m/s. What height is the pumpkin at when the speed is half its initial speed?

    asked by Anonymous on February 13, 2013
  46. Chemistry

    Equal volumes of 0.240 M AgNO3 and 0.140 M ZnCl2 solution are mixed. Calculate the quilibrium concentrations of Ag+, and Zn2+.

    asked by jina on April 8, 2011
  47. bioelectricity

    At a temperature of 10∘C, the concentrations of ions are: IonIntracellularExtracellular Na61485 K28010 Cl51485 The transmembrane potential is -30 mV. How many ion species (Na, K, or Cl) are NOT in equilibrium?

    asked by B on February 19, 2013
  48. chemistry

    Calculate Ke for the following(equilibrium concentrations given below substances) NH4SH(g) yields NH3(g) + H2S(g) + heat [.027] [.0234] [.209] Thank you!

    asked by mary on January 19, 2010
  49. health

    hat is physical stress? A. A physical reaction of the body to various triggers B. A physical reaction of the mind to various triggers C. A physical reaction of the soul to various triggers D. A physical reaction to the heart to various triggers i think its

    asked by noah on February 7, 2013
  50. Chemistry

    A 1.0-mL volume of 0.010 M H2SO3 is added to a mixture of 12 drops of 0.010 M HIO3, 8 drops of deionized water, and 1 drop of starch solution. a color change occured after 40 seconds. assuming 25 drops per mL for all solutions, determine the initial molar

    asked by Anonymous on February 22, 2013
  51. Chemistry URGENT! I really need help!

    Consider the following reaction occurring at 298K BaCO3(s)-> BaO(s) + CO2 (g) show that the reaction is not spontaneous under standard condition by calculating delta G rxn. I calculated delta G and got 219.7 kJ, now the question asks if BaCO3 is placed in

    asked by Trista Nigh on April 25, 2011
  52. Chemistry

    For the reaction 2CO2(g) + 5H2(g)C2H2(g) + 4H2O(g) H° = 46.5 kJ and S° = -124.8 J/K The standard free energy change for the reaction of 1.75 moles of CO2(g) at 328 K, 1 atm would be ___ kJ This reaction is (reactant, product) ____ favored under standard

    asked by John on November 20, 2017
  53. Chemistry

    Consider the following reaction occurring at 298K BaCO3(s)-> BaO(s) + CO2 (g) show that the reaction is not spontaneous under standard condition by calculating delta G rxn. I calculated delta G and got 219.7 kJ, now the question asks if BaCO3 is placed in

    asked by Trista Nigh on April 25, 2011
  54. Chemistry-DrBob222

    I got an answer of -1.34 x 10^3 KJ/mol. A 10.00 mL aliquot of 0.100 M NaOH is added to 15.00 mL of 0.100M HCl in a coffee cup calorimeter. The initial temperature of the two dilute liquids were both 25.0 degrees C and the final temperature of the mixture

    asked by Nevaeh on March 14, 2016
  55. Chemistry

    The decomposition of ozone may occur through the two-step mechanism shown below: step 1 O3 ----> O2 + O step 2 O3 + O ---> 2O2 The oxygen atom is considered to be: a catalyst or reaction intermediate? How am I supposed to be able to tell the difference

    asked by Marcus on February 19, 2013
  56. Chemistry

    There's reaction involving gas: Fe + H2SO4 -> Fe2(SO4)3 + H2O + SO2 How Fe2(SO4)3 is occur? I know the "2" comes from the ion of SO4, but I don't know where the "3" comes up. Is the Fe2(SO4)3 comes up from half-reaction method? Is the reaction occurs in

    asked by Jeremy on March 19, 2015
  57. Chemistry

    Phosphorous trichloride (PCl3) is produced from the reaction of white phosphorous (P4) and chlorine: P4(s) + 6Cl2(g) ! 4 PCl3(g) . A sample of PCl3 ofmass 280.7 g was collected from the reaction of 70.86 g of P4 with excess chlorine. What is the percentage

    asked by Jonathan on March 23, 2011
  58. Minoxidil

    So, I'm doing a research project for my chemistry class, and one of the parts that I have to answer is the chemical reaction of the substance that I'm researching. But there's a problem. I've searched every single website regarding minoxidil, but I cannot

    asked by Jude on May 28, 2012
  59. chemistry - Dr.Bob222 please help

    Hi Everyone, Anyone want to try giving these a shot? The right electrode in a cell is a piece of copper immersed in a 1.00 L solution of 0.0701 F copper sulfate. The left electrode is a galvanized nail (i.e., an iron nail that is completely coated with a

    asked by ajones51 on November 8, 2006
  60. chemistry

    3. When a mixture of 10.0 grams of acetylene (C2H2) and 10.0 grams of oxygen (O2) is ignited, the resulting combustion reaction produces CO2 and H2O. A) Write a balanced equation for this reaction. B) What is the limiting reactant? C) How many grams of C2,

    asked by tra on May 14, 2013
  61. Chemistry Lab Work Help!

    We used a buret today, and I don't get how to calculate volume. I have an initial reading of 49.97 and a final buret reading of 30.49. How do I get the volume? I thought I just subtracted the final from the initial, but someone said their tutor told them

    asked by Anonymous on November 13, 2015
  62. Chemistry

    The reaction of iron and water vapor results in an equilibrium reaction, 3 Fe(s) + 4 H2O(g) ¡ê Fe3O4(s) + 4 H2(g) and an equilibrium constant of 4.6 at 850¡ÆC. What is the concentration of Hydrogen present at equilibrium if the reaction is initiated

    asked by David on October 28, 2014
  63. Chemistry

    What is the value of the rate constant for a reaction in which 75.0 percent of the compound in a given sample decomposes in 80.0 min? Assume first order kinetics. Use the integrated rate law for a first order reaction. Remember at 75 percent reaction, 25

    asked by Bryan on September 20, 2012
  64. Chemistry

    What is the value of the rate constant for a reaction in which 75.0 percent of the compound in a given sample decomposes in 80.0 min? Assume first order kinetics. Use the integrated rate law for a first order reaction. Remember at 75 percent reaction, 25

    asked by Bryan on September 20, 2012
  65. chemistry

    0.197g of magnesium is burned in air 2Mg + O2 ---> 2MgO However, some of the magnesium reacts with nitrogen in the air to form Magnesium nitride instead : 3Mg + N2 --->Mg3N2 So you have a mixture of MgO and Mg3N2 weighing 0.315g.Determine what percentage

    asked by Chansa on May 4, 2016
  66. Science

    Assume you are speeding down the freeway at 75 mph. The car weighs 1500 kg and the effective force of the brakes is 14400 N. The car in front of you suddenly slows down, it takes 3 seconds for the car to do so. Your initial velocity was 33.53 and your

    asked by Athena on April 12, 2017
  67. Science, Physics

    Assume you are speeding down the freeway at 75 mph. The car weighs 1500 kg and the effective force of the brakes is 14400 N. The car in front of you suddenly slows down, it takes 3 seconds for the car to do so. Your initial velocity was 33.53 and your

    asked by Elizabeth on April 12, 2017
  68. Physics

    You are watching your friend play hockey. In the course of the game, he strikes the puck in such a way that, when it is at its highest point, it just clears the surrounding 2.96 m high Plexiglas wall that is 14.5 m away. (Ignore any effects due to air

    asked by Sam on July 6, 2015
  69. Chemistry

    A reaction is peformed in which 50 ml of .400M silver nitrate and 75 ml of .100M hydrochloric acid are mixed together. The initial temperature of the solutionn was 25 C and the final temperature was 27.2 C. What is the enthalpy, in kj/mol, for the

    asked by Lydia on November 18, 2012
  70. Physics

    An aluminum block slides along a horizontal surface. The block has an initial speed of 11.6 m/s and an initial temperature of 10.7°C. The block eventually slides to rest due to friction. Assuming all the initial kinetic energy is converted to heat energy

    asked by Gerry on February 9, 2011
  71. Science (Chemistry)

    A chemical system within a sealed 1 L reaction vessel is described by the following reversible reaction equation: 2H2S(g) 2H(g) + S2(g) If the equilibrium constant is 0.000 004 200 at 1103 K find: (a) the reaction quotient intially (b) the order of

    asked by Kibito on May 19, 2015
  72. Chemistry

    Which of the following can we predict from an equilibrium constant for a reaction? 1 The extent of a reaction 2 Whether the reaction is fast or slow 3 Whether a reaction is exothermic or endothermic a. 1 only b. 2 only c. 3 only d. 1 and 2 only e. 1 and 3

    asked by IBY on May 13, 2010
  73. Chemistry

    The following reaction has the following standard thermodynamic parameters: Reaction: C(g) + D(g)----> E(g) Delta H rxn=-26.1kJ/mol and Delta S rxn=-69.8J/(mol*K). Calculate the temperature at which the reaction becomes nonspontaneous.

    asked by Kay on January 31, 2012
  74. Chemistry

    The following reaction has the following standard thermodynamic parameters: Reaction: C(g) + D(g)----> E(g) Delta H rxn=-26.1kJ/mol and Delta S rxn=-69.8J/(mol*K). Calculate the temperature at which the reaction becomes nonspontaneous.

    asked by AAdd on March 21, 2014
  75. Chemistry

    The following reaction has the following standard thermodynamic parameters: Reaction: C(g) + D(g)----> E(g) Delta H rxn=-26.1kJ/mol and Delta S rxn=-69.8J/(mol*K). Calculate the temperature at which the reaction becomes nonspontaneous.

    asked by Kay on February 1, 2012
  76. Chemistry Need help ASAP

    A proposed mechanism for a reaction is: (i) A + B2 = AB2 Ea1 = 12 kJ/mol ƒ´H1 = 3 kJ/mol (ii) AB2 + C2 = ABC + BC Ea2 = 30 kJ/mol ƒ´H2 = 5.2 kJ/mol (iii) ABC + B2 = AB2 + BC Ea3 = 10 kJ/mol ƒ´H3 = -7.8 kJ/mol a) Which is the rate determining step?

    asked by Sarah on September 21, 2014
  77. chemistry

    A proposed mechanism for a reaction is: (i) A + B2 = AB2 Ea1 = 12 kJ/mol ƒ´H1 = 3 kJ/mol (ii) AB2 + C2 = ABC + BC Ea2 = 30 kJ/mol ƒ´H2 = 5.2 kJ/mol (iii) ABC + B2 = AB2 + BC Ea3 = 10 kJ/mol ƒ´H3 = -7.8 kJ/mol a) Which is the rate determining step?

    asked by Sarah on September 21, 2014
  78. Chemistry Need help ASAP

    A proposed mechanism for a reaction is: (i) A + B2 = AB2 Ea1 = 12 kJ/mol ƒ´H1 = 3 kJ/mol (ii) AB2 + C2 = ABC + BC Ea2 = 30 kJ/mol ƒ´H2 = 5.2 kJ/mol (iii) ABC + B2 = AB2 + BC Ea3 = 10 kJ/mol ƒ´H3 = -7.8 kJ/mol a) Which is the rate determining step?

    asked by Sarah on September 21, 2014
  79. Chemistry

    This problem is 1st order for half life. How long would it take for the concentration of cyclopropane to decrease to 50% of its initial value? to 25% of its initial value? Rate constant is 9.2/s I set up like this... t1/2= 0.693/9.2/s= 0.075s at 50% I

    asked by Chris on January 21, 2013
  80. Chemistry

    Predict the product(s) for the following reaction: H2SO4(aq) + KOH(aq) --> Choose one answer. a. K(s) + H2(g) + SO3(g) b. K2SO4(aq) + H2O(l) c. No reaction occurs d. K2S(aq) + H2O(l) e. KSO4(aq) + H2O(l) I keep getting: K2SO4(aq) + 2H2O(l) which isn't at

    asked by Toby on July 24, 2011
  81. chem 100

    For the reaction CH3OH(g)←→CO(g) + 2H2(g), a. Determine ΔHo and ΔSo for the reaction at 298K b. Determine the entropy change for the surroundings assuming that they are at 298 K. What does this result tell you? c. Calculate ΔGo at 298 from tabulated

    asked by Mall on April 19, 2015
  82. chemistry

    Which of the answer choices correctly describes an action that will increase the solubility of a solid solute in water? cool the solution increase the pressure heat the solution decrease the pressure Examine the statement. The energy required to break the

    asked by PLEASE help on September 22, 2017
  83. Chemistry

    can anybody think of a reaction that involves benzyl acetate? formula is CH3COOCH2C6H5 i already have most of the synthesis's but i really need a reaction that involves this ester as a reactant NOT a product. thanks :) Why don't you just cleave the ester

    asked by steff on December 21, 2006
  84. physics

    A soccer ball is kicked with an initial horizontal velocity of 16 m/s and an initial vertical velocity of 17 m/s. 1) What is the initial speed of the ball? 2) What is the initial angle θθ of the ball with respect to the ground? 3) What is the maximum

    asked by Hallie on September 11, 2016
  85. chemisrty - ICE CHART DEPOSTION

    How do i fill out an ICE chart when i am only given an initial concentration of one reactants and an equilibrium of another reaction? inital 0.045 HNO2(aq) Equilibrium 0.0043 H3O+(aq) NO2(aq) - no information my first thought was to sqaure root .0043 mol/l

    asked by Tara on November 22, 2012
  86. chemisrty - ICE CHART DEPOSTION

    How do i fill out an ICE chart when i am only given an initial concentration of one reactants and an equilibrium of another reaction? inital 0.045 HNO2(aq) Equilibrium 0.0043 H3O+(aq) NO2(aq) - no information my first thought was to sqaure root .0043 mol/l

    asked by Tara on November 22, 2012
  87. math

    a particle M oscillators (that is, moves back and forth) in a straight line along the horizontal axis. the position of M is given by: s(t) = 4 + 2 sin(2t) (1) Find the velocity (v) and acceleration (a) functions. (2) Find the initial position, initial

    asked by memo on August 13, 2011
  88. Physics

    A 2.0 lb block is given an initial speed of 4.0 ft/sec up an inclined plane starting from a point 2.0 feet from the bottom as measured along the plane. If the plane makes an angle (theta = 30 degrees) with the horizontal and the coefficient of friction is

    asked by Nora on March 12, 2015
  89. physics

    A ball is thrown upward off the top of a 30-meter high building. 10 meters below the top of the roof, is the top of a window, which is 2 meters high. How long (time) does it take for the ball to pass from top to bottom of the window? What I have so far is:

    asked by Dreskillz89 on September 28, 2009
  90. chemistry

    Calculation of )Hf0 for Mg2+(aq.) 1. Assume the heat capacity of the final solution is 3.92 J K-1 g-1. Using the mass of the HCl solution, calculate qcontents from equation (4.6). Calculate qsystem from equation (4.5). 2. Calculate the moles of Mg2+

    asked by Narash on March 25, 2011
  91. AP Chemistry

    Q - An electrochemical reaction occurs between an unknown element and zinc. The half-cell reaction for the zinc is: Zn(s) → Zn2+(aq) + 2e− The cell potential for the reaction is Eºcell = 1.83 V. Is the reaction spontaneous or nonspontaneous? Explain.

    asked by Jessica AP Chemistry on July 6, 2016
  92. chemistry

    Which of the following statements is true about the nucleus? Only the strong nuclear force holds the nucleus together. The strong nuclear force and the residual strong force hold the nucleus together. The presence of neutrons, the strong nuclear force, and

    asked by robstone on May 20, 2015
  93. Chemistry

    -Consider the reaction when aqueous solutions of silver(I) nitrate and manganese(II) chloride are combined. The net ionic equation for this reaction is? -Consider the reaction when aqueous solutions of cobalt(II) sulfate and lead(II) nitrate are combined.

    asked by Natalie on March 6, 2018
  94. chemistry

    How much Tris-Acetate-EDTA (TAE) stock buffer (3.25 M) is required to make 400 ml of solution that has a concentrations of 250 mM? How much water?

    asked by Abass on July 8, 2013
  95. Chem

    One of my questions asks, when can you conclude about the relative equillibrium concentrations of CrO4^2- in each of the colutions 0.1 M K2Cr2O7 and 0.1 M K2CrO4? Im really confused by this question. Could someone clarify it for me? Thanks :)

    asked by Lena on July 22, 2009
  96. chemistry

    At a certain temperature, the concentrations of NO and NH3 are equal, and the concentration of H2o and o2 are 2.0M and 3.0M respectively. What is the value of Keq at this temp? The equation is 5O2+4NH3--> 4NO+6H20

    asked by K on March 24, 2013
  97. Chemistry

    Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points. CoCl3 K2CO3 KNO3

    asked by Megan on January 30, 2015
  98. chemistry

    H2 + I2 2 HI. Looking for Keq: Complete the equation. Assume all concentrations are equilibrium constants in mol/L , M Temp in Celcius = 25 [H2] = .355 [I] = .388 [HI] = .0922 K eq = ??

    asked by Sarah on November 13, 2011
  99. Chemistry

    Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points: Li2SO4 K3PO4 LiNO3

    asked by Dustin on November 6, 2014
  100. chemistry

    Calculate the concentrations of all species in a 1.22 M Na2SO3 (sodium sulfite) solution. The ionization constants for sulfurous acid are Ka1 = 1.4× 10–2 M and Ka2 = 6.3× 10–8 M.

    asked by anon on October 30, 2014