The reaction A -->B---> C is called a _______ reaction? Consecutive parallel competing stepwise

30,179 results
  1. chemistry

    Which statement describes a chemical reaction at equilibrium? A. The forward reaction happens slightly faster than the reverse reaction. B. The reaction has stopped because all reactants have been used up. C. The forward reaction happens at the same rate

  2. Science

    Hydrogen peroxide can be prepared in several ways. One method is the reaction between hydrogen and oxygen, another method is the reaction between water and oxygen. Calculate the ΔG°rxn of each reaction below? 1) H2(g) + O2(g) H2O2(l) ΔG°rxn=? (in kJ)

  3. Chemistry--need help!

    1. Which of the following statements is true about reaction rates? a. Reaction rates can be predicted from the coefficients of the balanced equation. b. Reactants usually disappear faster than the products appear. c. Reactants usually disappear slower than

  4. AP CHEMISTRY

    Phosphoric acid is triprotic acid (three ionizable hydrogens). The values of its stepwise ionization constants are Ka1= 7.5E-5, Ka2= 6.2E-8, and Ka3= 4.2E-13 1) Write the chemical equation for the first ionization reaction of phosphoric acid with water

  5. chemistry

    If you need to multiply the following reaction by 2 to be an intermediate reaction in a Hess's law problem, what would be the final value for the enthalpy of reaction you use for this intermediate reaction? C2H4 + 3 O2 2 CO2 + 2 H2O, H = -1410 kJ

  6. Chemistry 30

    Consider the following reaction at equilibrium: 4NH3(g) + 5O2(g) ↔ 4NO(g) + 6H2O(g) In what direction will the following changes force the reaction? a) Addition of O2 b) Reduction of the amount of water vapour c) Increase in the pressure d) Decrease in

  7. Chemistry - Science (Dr. Bob222)

    The following reaction has a positive value of ΔG°. 2H2O(g) → 2H2(g) + O2(g) Which of the following statements must be true? A. The reaction is slow. B. The reaction will not occur. That is, when H2O(g) is introduced into a flask, no O2 or H2 will form

  8. Chemistry

    If a catalyst is added to a system at equilibrium and the temperature and pressure remain constant there will be no effect on the: (1) rate of the forward reaction (2) rate of the reverse reaction (3) activation energy of the reaction (4) heat of reaction

  9. science

    what type of reaction is this 2h2o2 (l) -> 2h2o(l)+ o2 (g) a.single replacement reaction. b.decomposition reaction. c.acid-base neutralization reaction. d.no reaction.

  10. Chemistry

    In which direction will the net reaction proceed. X(g) + Y(g) Z(g) .. Kp = 1.00 at 300k for each of these sets of initial conditions? 1) [X] = [Y] = [Z] = 1.0 M a] net reaction goes to the left [this one?] b] net reaction goes to the right c] reaction is

  11. Chemistry

    35. In a calorimeter, the energy content of a substance is calculated from a measure of the temperature change in a known mass of a. iron b. air c. water d. steel C? 36. A decrease in the reactant concentration, per unit time, in a reaction is a measure of

  12. Chemistry

    1.) The the following reaction is: BaCO3 --> BaO + CO2 Decomposition reaction Single replacement reaction Combustion Reaction Synthesis Reaction Double replacement reaction 2.) When magnesium is burned in the presence of oxygen, it produces magnesium oxide

  13. Chemistry

    Identify the correct statement for the following reaction: Br2 (l) → Br2 (g) ΔH° = 30.9 kJ ΔS° = 93.2 J/K A) The reaction is always spontaneous. B) The reaction is never spontaneous. C) The reaction is at equilibrium; therefore, ΔG° = 0. D) The

  14. Biology

    In a chemical reaction, the forward rate is greater than the reverse rate. Which statement about the reaction is correct? The reaction is reversible. The reaction will continue until the reactant is used up. The concentrations of the reactant and the

  15. Chemistry-rate laws

    1. Determine the overall reaction order for the reaction whose rate law is as follows: rate=k[O3][ClO]: a. 0 b. 1 c. 2 *** d. 3 2. For the reaction (A→2B) whose rate law is rate=k, which of the following will change the value of k? a. adding a catalyst

  16. Chemistry

    For a one step reaction, the activation energy for the forward reaction is 40.0 kJ/mol and the enthalpy of reaction is -20.0 kJ /mol. Which statement below is true? a. The activation energy of the forward reaction would be affected to a greater extent than

  17. chemistry

    The enthalpy change for the following reaction is -483.6 kJ: 2H2(g) + O2(g) = 2H2O(g) Therefore, the enthalpy change for the following reaction is _______ kJ: 4H2(g) + 2O2(g) = 4H2O(g)

  18. chemistry

    A first order reaction and a separate second order reaction both have the same rate of reaction. What is the effect on the rate of reaction for each reaction if the concentrations of reactants in both reactions are halved?

  19. chem help!

    Which statement is true about a reaction at equilibrium? A. The reaction is not reversible. B. The reaction concentrations of the reactants and products are always equal. C. The reaction rates of the forward and reverse reaction are always equal. D. The

  20. organic chemistry

    Michael & Aldol Condensation Reaction We are preparing an a,b-unsaturated ketone via Michael and aldol condensation reactions. The reactants are trans-chalcone and ethyl acetoacetate (in ethanol and NaOH). This creates

  21. Chemistry

    Consider the reaction: 2N2O (g) 2N2 (g) + O2 (g) The values of Kc at different temperatures are: Which statement is correct at a higher temperature? A. The forward reaction is favoured. B. The reverse reaction is favoured. C. The rate of the reverse

  22. 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

  23. Chemistry Help!!

    Types of Reactions Worksheet Balance the following equations and indicate the type of reaction taking place: 1) 2 NH3 + 3 I2  N2I6 + 3 H2 Type of reaction: ____________________ 2) 3 Ca(OH)2 + Al2(SO4)3  3 Ca(SO4) + 2 Al(OH)3 Type of reaction:

  24. (11) Chemistry - Science (Dr. Bob222)

    In the following hypothetical reaction A + B → C + D, the equilibrium constant, Keq is less than 1.0 at 25°C and decreases by 35% on changing the temperature to 45°C. What must be true according to this information? A. The ΔH° for the reaction is

  25. science

    In a chemical reaction, the forward rate is greater than the reverse rate. Which statement about the reaction is correct? The reaction is reversible. The reaction will continue until the reactant is used up. The concentrations of the reactant and the

  26. Chemistry

    I'm supposed to balance a redox reaction that occurs in an acidic solution. I already balanced it(h**p://img148.imageshack.us/img148/4304/redoxht8.jpg), but how do I tell if a half-reaction is oxidation or reduction? I know an oxidation reaction loses

  27. Biochem

    Consider the malate dehydrogenase reaction from the citric acid cycle. Given the following concentrations, calculate the free energy change for this reaction at 37.0 °C (310 K). ΔG°\' for the reaction is 29.7 kJ/mol. Assume that the reaction occurs at

  28. Chemistry

    Which statement about this reaction is FALSE? AgNO3 + NaCl -> AgCl + NaNO3 A. This is one kind of metathesis reaction, where molecules exchange atoms. B. This reaction produces a gas. C. This is a precipitation reaction. D. The equation is balanced

  29. chemistry

    Consider the following reaction: 2HBr(g)---> H_2(g) + Br_2(g) B)In the first 15.0s of this reaction, the concentration of HBr dropped from 0.510M to 0.455M. Calculate the average rate of the reaction in this time interval. C)If the volume of the reaction

  30. Chemistry

    Draw a reaction profile (diagram of energy vs reaction coordinate) for a hypothetical reaction AB +C A+BC in which the foward reaction has an activation energy of 100kJ mol-1 and the backward reaction has an activation energy of 75kJ mol-1. (ii). a

  31. Chemistry

    Given the reaction system; 2 NO (g) + O2 (g) -> 2 NO2 (g) Write a brief explanation for each of the following statements in terms of the collision model and/or reactions mechanisms. (1)Increasing the concentration of NO (g)makes the reaction go faster.

  32. chemistry

    can i please get some help with this? For the equilibrium reaction involving the formation of ammonia, which can be described by the reaction below, describe the effect of adding H2 gas to the reaction, increasing the pressure in the reaction, and

  33. science

    When Q < K, what can you conclude about the reaction? A. The reaction is not yet at equilibrium, and the reaction will proceed in the forward direction. B. The reaction is not yet at equilibrium, but the direction of the reaction must be experimentally

  34. chemistry

    For a one step reaction, the activation energy for the forward reaction is 40.0 kJ/mol and the enthalpy of reaction is -20.0 kJ /mol. Which statement below is true? a. The activation energy of the forward reaction would be affected to a greater extent than

  35. chem

    1) When a mixture of potassium chlorate and an appropriate catalyst is heated in an open test tube, potassium chloride and oxygen gas are produced. This reaction is not reversible, because a. the system reaches equilibrium b. the reaction does not go to

  36. Chemistry

    In a reaction in which A + B yields AB, the reaction is referred to as a _________. A. decomposition reaction B. double-replacement reaction C. combustion reaction D. composition reaction

  37. Science

    What is a synthesis reaction? a reaction that occurs when one element within a compound is exchanged with another element a reaction that occurs when a single substance breaks apart and forms two or more new substances a reaction that occurs when a

  38. chemistry

    During a chemical reaction, if Q = K, what can be said about the reaction? A. The reaction still proceeds in both directions, but the net result is that the reactant and product concentrations do not change. B. The amount of product is always equal to the

  39. Chemistry Question

    The reaction of quicklime (CaO) with sulfur dioxide (SO2) is an important reaction for reducing SO2 emissions from coal-fired power plants: CaO(s) + SO2(g) → CaSO3(s) This reaction is an example of: A. a precipitation reaction B. an electrolysis reaction

  40. chemistry

    Choose all of the following statements about the equilibrium constant K that are true: (a) If the K value for a reaction is > 1 then Go must be negative for this reaction (b) A large value for K implies there is a strong driver for the reaction to proceed

  41. chem

    Check the correct statements for the above reaction. Choose at least one answer. a. The reaction is exothermic. b. The reaction is endothermic. c. The change in entropy is positive. d. The change in entropy is negative. e. The reaction is at equilibrium.

  42. Chemistry

    What does adding a catalyst to a reaction do? Select all that apply. increase the amount of each product formed by the reaction lower the activation energy of the reaction (correct) alter the orientation of reactants in the reaction increase the rate of

  43. Chemistry

    Which of the following must have been true about the reaction that produced this net ionic equation? H3O+ (aq) + OH−(aq) --> 2H2O(l) A. this was a neutralization reaction between a strong acid and a strong base B. this was a chemical reaction that

  44. Chemistry

    In an endothermic reaction at equilibrium, what is the effect of raising the temperature? The reaction makes more products the reaction makes more reactants*** the reaction is unchanged the answer cannot be determined

  45. Chemistory

    The reaction has an equilibrium constant of = 0.154. If 6.60 of , 4.30 of , and 11.60 of are added to a reaction vessel with a volume of 5.30 , what net reaction will occur? A-The reaction will proceed to the left to establish equilibrium. B-The reaction

  46. chemistry

    The formation of nitroanalyine (an important intermediate in dyes, called ‘fast orange’) is formed from the reaction of ortho-nitrochlorobenzene (ONCB) and aqueous ammonia. (See Table 3-1 and Example 9-2.) The liquid-phase reaction is first-order in

  47. Biology(Anatomy&Physiology)

    1)Which organelle makes most ATP 2)The chemical reaction that joins two amino acids is called 3)In a single molecule of water which type of bond holds the H to the O? 4)Which type of chemical bond results from the transfer of an electron from one atom to

  48. Chemistry

    The energy necessary to start a chemical reaction is called the _______ energy. a)exothermic b)activation c)endothermic d)combustion

  49. music

    Smooth, stepwise movement within a melodic phrase, subphrase, or statement is known as _______ motion

  50. Chemistry

    In a certain chemical reaction, 20.40kJ of heat are evolved. The volume of the reaction is 36.8dm^3 and that of the product is 9.6dm^3. Calculate the change in internal energy for the reaction. Assume the reaction is at ATM pressure.?

  51. Biology

    Okay so if i have two enzyme catalyzed reactions: 1) delta g of the ES = -22kJ/mol 2) delta g od the ES = 42 kJ/mol Is this first reaction going to have a higher reaction rate because the of the negative delta g, because doesnt a negative delta g give you

  52. chemistry

    For a one step reaction, the activation energy for the forward reaction is 40.0 kJ/mol and the enthalpy of reaction is -20.0 kJ /mol. Which statement below is true? a. The activation energy of the forward reaction would be affected to a greater extent than

  53. Chemistry

    The ΔH of the reaction below is -575.13 kJ. Is this reaction spontaneous? 2ZnS + 3O2 + C → 2SO2 + 2Zn + CO2 A. It is not because the ΔH of the reaction is negative. B. It is because the ΔH of the reaction is negative. C. It depends on the temperature

  54. chemistry

    Hi, I am trying to find the pH of a buffer I created and then added NaOH to. This is my data: total volume of solution 34.2 mL [NaOH] before reaction 6.0 [HOAc] before reaction .8 M [OAc-] before reaction .4 M [HOAc] after reaction 0 M [OAc-] after

  55. Chemistry

    The change in enthalpy for the forward reaction is -91KJ/mol CO(g) + 2H2(g) CH3OH(g) 1. The forward reaction is? A. Endothermic B. Exothermic ** 2. If the reaction is at equilibrium and then was heated _____ CH3OH would be present after the reaction

  56. Chemistry

    Hi Dr. Bob, I am quite stumped on how to figure out when chemical equations have a REACTION or NO REACTION. I have read the material in my textbook and even took out a chemistry books for the "Utterly Confused" to try to figure this out. Example: Zn(s) +

  57. Chemistry

    The equilibrium constant Kc for the following reaction is equal to 0.20 at 250°C. Calculate the equilibrium constant Kp for the reverse reaction at the same temperature. COCl2 (g) = CO (g) + Cl2 (g) My Answer: To find the reverse reaction of Kc, it should

  58. Chemistry(Please check)

    1) A catalyst alters the rate of a reaction by a. changing the products in the reaction. b. increasing the activation for the reaction. c. always providing a surface on which the molecules react. d. providing an alternate pathway for the reaction. e.

  59. chemistry help

    During a chemical reaction, if Q = K, what can be said about the reaction? A. The reaction still proceeds in both directions, but the net result is that the reactant and product concentrations do not change. B. The amount of product is always equal to the

  60. Chemistry

    You carry out an exothermic reaction inside a Styrofoam cup calorimeter, using a temperature probe to monitor the temperature throughout the reaction. You find that the temperature increases 7.40 °C during the reaction. The specific heat of the reaction

  61. Chemistry...HELP!!!!

    In a reaction in which A + B yields AB, the reaction is referred to as a _________. A. decomposition reaction B. double-replacement reaction C. combustion reaction D. composition reaction i think is a

  62. chemistry

    What kind of reaction occurs when a molecule of glucose reacts with oxygen to give carbon dioxide and water? a.exothermic reaction b.endothermic reaction c.synthesis reaction d.irreversible reaction

  63. Chemistry

    The lab we are doing is: Determining the ENTHALPY of a Chemical Reaction. There are three reactions. Reaction 1: NaOH + HCl, Reaction 2: NaOH + NH4Cl, and Reaction 3: HCl + NH3. I found the max temp, initial temp, and temp change of each reaction. Can you

  64. chemistry

    3HgO→2Hg+O2 Which of the following can definitely be concluded from the equation and heat of reaction above? A. The reaction is spontaneous. B. The reaction is non-spontaneous. C. The reaction is endothermic. D. The reaction is exothermic. E. None of

  65. Chemistry

    Which of the following is true about a thermonuclear reaction: A- The rxn will always have 3 intermediate steps B- The reaction will have low activation energy C- The reaction will always be 3rd order D- The reaction is always spontaneous

  66. Chemistry

    What type of reaction is involved in the making of Polypropylene? Would it be a synthesis reaction? The final step is a polymerization reaction. Before that, the propylene (C3H6) is made in a cracking reaction from heavier hydrocarbons. Thank you. :)

  67. Chemistry

    AgNO3 + NaCl -> AgCl + NaNO3 Which statement about this reaction is FALSE? A. This is one kind of metathesis reaction, where molecules exchange atoms. B. This reaction produces a gas. C. This is a precipitation reaction. D. The equation is balanced.

  68. Chemistry Check!

    1. Gibb's Free Energy is a. the spontaneous energy of a reaction *** b. the chemical energy that can be used for performing work c. the non-spontaneous energy of a reaction d. the amount of activation energy needed for a reaction to start 2. Which reaction

  69. Chemistry

    Given the reaction system; 2 NO (g) + O2 (g) -> 2 NO2 (g) Write a brief explanation for each of the following statements in terms of the collision model and/or reactions mechanisms. (1)Increasing the concentration of NO (g)makes the reaction go faster.

  70. chem due soon

    The ΔH of the reaction below is -575.13 kJ. Is this reaction spontaneous? 2ZnS + 3O2 + C → 2SO2 + 2Zn + CO2 A. It is not because the ΔH of the reaction is negative. B. It is because the ΔH of the reaction is negative. C. It depends on the temperature

  71. chemistry

    Reaction 1: I2(aq)Cu^+2(aq) Ag^+(aq)Br2(aq) Column 1---Column 2---Column 3---Column 4---Column 5 I-(aq)---X---X---T---T Cu(s)---T---X---T---T Ag(s)---X---X---X---T Br-(aq)---X---X---X---X Reaction of metals and solution of ions Reaction 2:

  72. chemistry

    I have two questions that I really don't understand. The first one is: A reaction proceeds with delta H=-10kJ/mol. The energy of activation of the uncatalyzed reaction is 150kJ/mol, whereas it is 100kJ/mol for the uncatalyzed reaction. How many times

  73. Chem II

    The reaction A -->B---> C is called a _______ reaction? Consecutive parallel competing stepwise

  74. Chemistry - Rates

    For a particular reaction, the rate constant is 2.32 ✕ 10−3 M/s at 185°C and 3.70 ✕ 10−3 M/s at 235°C. What is the activation energy for this reaction? _______ kJ/mol

  75. ~Chem

    I was looing over this question and the answer I got was not correct, I noticed that somone already posted this question up before but maybe if I provide the answer I could get an understanding of the steps. @462degrees the reaction heat + 2NOCl 2NO + Cl2

  76. chemistry

    State whether each of the following will increase,decrease or unchange when catalyst is added to the reaction and give an explanation for your answer please a) rate of reaction b)activation energy c)reaction enthalpy d)equilibrium of reaction

  77. College Chem

    4. Write the balanced equation for CH4+Cl2„_CH2Cl2+HCl6. For the reaction in problem 4, Heat of Reaction = -118.3 kcal/mol. Identify whether this is an exothermic or endothermic reaction. Calculate the Heat of Reaction when 6.00 g of Cl2 are used in the

  78. chemistry

    Can someone explain this to me? In the reaction: --> AgCl(s) In the reaction HC2h302 + H20

  79. help help help chemistry

    why will no one answer this question? For a one step reaction, the activation energy for the forward reaction is 40.0 kJ/mol and the enthalpy of reaction is -20.0 kJ /mol. Which statement below is true? a. The activation energy of the forward reaction

  80. chemistry

    The activation energy of a reaction is typically determined by calculating the rate constant for the reaction at two temperatures and then manipulating the Arrhenius equation. If you determine the reaction rate constants for a particular reaction to be

  81. Chemistry

    Consider the reaction 2A (g) + B (g) --> C (g) At 300K temperature, pressure of A and B are 2*10^5 Pa. The temperature is kept constant and let the reaction occur. After 5 mins the total pressure of the system os 3.5*10^5 Pa. Question : When the pressure

  82. General Chemistry

    Sodium Hydroxide reacts with hydrobromic acid to yield two products. Write out a balanced molecular reaction, overall ionic reaction and a net ion reaction. I have the molecular reaction, which I got: NaOH + HBr -> NaBr + H20 Correct? Any help with the

  83. Electrochem

    I have a table of standard potentials in water that gives a number of reactions and their e*reduction. Say I'm looking for the reaction Al(s) --> Al+3 + 3e-, but the book gives me the reaction Al+3 + 3e- --> Al(s) and a E*red value of -1.68. If this were

  84. chemistry

    Consider the following reaction in a closed reaction flask. If 0.600 atm of gas A is allowed to react with 1.20 atm of gas B and the reaction goes to completion at constant temperature and volume, what is the total pressure in the reaction flask at the end

  85. Chemistry

    I am trying to figure out how to calculate the reaction rate. In my question the reaction rate is: 1/2x molarity of sodium thiosulfate/reaction time Then I have to compare the rates of runs 1-3 and determine the orders of the reaction. Do I only find the

  86. chemistry

    The following reaction was carried out in a 2.00 reaction vessel at 1100 : C+H2O -> C)+H2 If during the course of the reaction, the vessel is found to contain 7.00mol of C, 13.3mol of H2o, 3.80mol of CO, and 7.20mol of H2, what is the reaction quotient ?

  87. Organic Chemistry

    The Diels-Alder reaction is classified as a: A. polar reaction B. radical reaction C. substitution reaction D. pericyclic reaction E. rearrangement reaction

  88. Chemistry

    Recall that all aqueoous solutions contain_____. Water can also undergo ____. This process is called the ______of water. The reaction can be written as: Notice the double arrow in the reaction. This indicates that the reaction is_____. However, only a tiny

  89. organic chemistry

    Michael & Aldol Condensation Reaction We are preparing an a,b-unsaturated ketone via Michael and aldol condensation reactions. The reactants are trans-chalcone and ethyl acetoacetate (in ethanol and NaOH). This creates

  90. organic chemistry

    Michael & Aldol Condensation Reaction We are preparing an a,b-unsaturated ketone via Michael and aldol condensation reactions. The reactants are trans-chalcone and ethyl acetoacetate (in ethanol and NaOH). This creates

  91. chemistry

    For the reactions that occurred spontaneously in the individual tables, balance these reactions assuming they are in an acidic solution. Reaction 1: Cu I^- Ag Br^- Reaction 2: Zn Pb Cu Ag Reaction 3: Cl2 Br2 I2 Reaction 1 I 2(aq) Cu2 + (aq) Ag + (aq) Br2

  92. science

    A + B -----> C is an example of a A) double-displacement reaction B) synthesis reaction C) single-displacement reaction D) redox reaction E) decomposition reaction

  93. Chem18

    Coal can be used to generate hydrogen gas by this endothermic reaction: C(s) + H2O(g) CO(g) + H2(g) If this reaction is at equilibrium, which of these stresses would increase the formation of hydrogen gas? (choose ALL of the possible answers - there may be

  94. chemistry

    For a one step reaction, the activation energy for the forward reaction is 40.0 kJ/mol and the enthalpy of reaction is -20.0 kJ /mol. Which statement below is true? a. The activation energy of the forward reaction would be affected to a greater extent than

  95. Chemistry

    The reaction between 0.045 g of calcium with an excess of water was carried out in an ice calorimeter as used in this lab. The volume of water in the calorimeter decreased by 0.18 mL during the reaction a) Write the equation for the reaction which occurs.

  96. Science

    When yeast carries out a reaction called fermentation, hydrogen ions are released into the surrounding substance. What could you mix with the substance to prove that this reaction is taking place and how do you know it would work?

  97. Organic Chem Help

    You react hydrogen iodine with 3-methylhex-3-ol. a) write the overall equation for the reaction. b) do you expect this reaction to go by an SN1 or an SN2 mechanism? Explain your answer. c) give a detailed reaction mechanism for the reaction showing all

  98. organic chemistry

    Something that isn't consumed by the reaction (so say A) is dissolved at the same time as something that is consumed by the reaction (B) in a solvent, so that they are in the same phase...what is this reaction an example of? What is the most pervasive

  99. Biochemistry

    Consider the malate dehydrogenase reaction from the citric acid cycle. Given the following concentrations, calculate the free energy change for this reaction at 37.0 °C (310 K). ΔG°\' for the reaction is 29.7 kJ/mol. Assume that the reaction occurs at

  100. Organic Chemistry

    Hello, I have done an experiment in Organic Chemistry called :SN1 Reaction: Synthesis of t-amyl chloride from t-amyl alcohol, there are some questions that I am unsure about, 1) What are the 2 rules of HCl in this reaction? Can you use NaCl instead of HCl

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