Chemical kinetics Questions and Answers

Given that 2 Al + 6 HCI → 2 AICI3 + 3H₂ How many moles of hydrogen are produced if we start from 1.2 mol Al and 2.2 mol HCI? mol H₂ How many moles of excess reactant are left over? mol

What happens first during cellular respiration? A. The movement of small organic molecules into a mitochondrion O B. The breakdown of food molecules into smaller organic molecules O C. The formation of many molecules of ATP D. The breakdown of small organic molecules into carbon dioxide

From the reaction equation below, if the average rate of disappearance of oxygen gas is 0.035 mol/Ls, what is the average rate of appearance of sulfur trioxide gas? * (1 Point) 2 SO₂(g) + O₂(g) -> 2 SO3(g) 0.070 mol/(Los) 0.0175 mol/(Los) 0.0070 mol/(Los) 2.035 mol/(Los)

Product, the rate expression is given by For A + B + C Rate = K[A] [B] What is the rate of initial reaction if the reaction is started with 1 mol/L each of A, B and C. K = 1 x 10-6 mol-1 Ls-1. A B C D 10-6 mol L-1 s-1 10-3 mol L-1 s-1 10-2 mol L-1 s-1 10-4 mol L-1 s-1

Reaction intermediates are never actually observed in the products because They are produced in one step and then used up in a later step They disappear before we can see them They turn back into reactant molecules

At a certain temperature the rate of this reaction is second order in H3PO4 with a rate constant of 0.297 M 2H₂PO4 (aq) → P₂O, (aq) + 3H₂O (aq) Suppose a vessel contains H3PO4 at a concentration of 1.44 M. Calculate the concentration of H3PO4 in the vessel 8.80 seconds later. You may assume no other reaction is important.

Consider two reactions, one that is second order and one that is third order. Which best describes the effect on the reaction rates by INCREASING the concentration of all reactants? The rate increases for only the second-order reaction. The rates decrease for both reactions. The rates increase for both reactions. The rate decreases for only the third-order reaction.

There are molecules in 30.0 grams of NH3. Select the correct answer below: 1.06 x 1024 molecules 1.03 x 1025 molecules 3.42 x 1023 molecules 1.81 x 1025 molecules

Using photoelectron spectroscopy, the ionization energy of the least tightly bound valence electron on F was determined to be 17.4 eV. Calculate the Zeffective for this electron.

Fluorine-18, which has a half-life of 110 min, is used in PET scans. If 200 mg of fluorine-18 was shipped, and it took 5.5 hours for it to arrive, how many milligrams of the radioisotope are still active? (5.4) Cerium -141, used to measure blood flow to the heat, has a half-life of 32.5 days. (5.2, 5.4) a. Write the balanced nuclear equation for the beta decay of cerium-141. b. How many days are required for 28 mg of cerium-141 to decay to 1.75 mg of cerium-141?

The graph below is a potential energy diagram for the hypothetical reaction: A + B - C + D a. Is the forward reaction endothermic or exothermic? Calculate the value of AH for this reaction. b. What is the value of the potential energy of the activated complex?

At a certain temperature the rate of this reaction is first order in SO3 with a rate constant of 0.0884 s 2SO3 (g)2SO₂(g) + O₂(g) Suppose a vessel contains SO3 at a concentration of 1.09 M. Calculate the concentration of SO3 in the vessel 9.30 seconds later. You may assume no other reaction is important.

Consider the following reaction in aqueous solution: 5Br- (aq) + BrO3-(aq) + 6H+ (aq) → 3Br₂(aq) + 3H₂O(l) If the rate of disappearance of Br (aq) at a particular moment during the reaction is 3.5x10^-4 M/s what is the rate of appearance of Br₂(aq) at that moment?

The reaction A+B ⇒C+D rate = k[A][B]² has an initial rate of 0.0480 M/s. What will the initial rate be if [A] is halved and [B] is tripled? initial rate: M/s What will the initial rate be if [A] is tripled and [B] is halved? initial rate: M/s

For the following equilibrium equation, choose the correct conjugate acid-base pair. HSO4 (aq) + HPO4² (aq) + SO4² (aq) + H₂PO4 (aq) a) HSO4 (acid) and S2 (conjugate base) b) HPO42- (acid) and H₂PO4 (conjugate base) c) HSO4 (base) and SO42 (conjugate acid) d) HSO4 (acid) and HPO42 (conjugate base)

Radioactive iodine-131 (t₁/2 = 8.0 days) decays to form xenon-131 by emission of a ß particle. How much of each isotope is present after each time interval if 82 mg of iodine-131 was present initially: (a) 8.0 days; (b) 32 days?

For an equilibrium reaction with K = 1.2 × 108, the forward rate constant was found to be 3.5 × 10³. What is the value of the reverse rate constant? 6.0 x 10-5 3.4 x 10² 4.2 x 1013 3.5 x 105 2.9 × 10-3

If a first order reaction is initiated with 1.50 M concentration of a reactant, what concentration remains after six half-lives? 0.0234 M 0.0750 M 0.0938 M 0.0625 M 0.0156 M

Consider the reaction 2A + B ----- 2 C + D + 25.0 kJ with energy of activation of 75.0 kJ. What is the energy of activation for the reaction 2 C + D --- 2 A+B at the same temperature? A-75,0 kJ B. 100 kj C. 50.0 kj D. 75.0 kj E. 30.4 torr

Gaseous butane (CH, (CH₂), CH₂) will react with gaseous oxygen (0₂) to produce gaseous carbon dioxide (CO₂) and gaseous water (H₂O). Suppose 10.5 g of butane is mixed with 26. g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Round your answer to 2 significant digits.

Consider the rate = k[H₂SeO3][-]³[H+]2. Which statement best describes the rate law 2nd order in H* and 5th order overall First order in IT and 3rd order overall First order in H₂SeO3 and 6th order overall 2nd order in H and 4th order overall 3rd order in I and 4th order overall

Carbon tetrachloride can be prepared by reacting CHCl3 and Cl2 according to the balanced reaction CHCl3(g) + Cl2(g) → CCl4(g) + HCl(g) the rate law is rate=k[CHCl3][Cl2] Based on the following steps, which one is the rate limiting step. 1) Cl₂(g) →2Cl(g) 2) CI(g) + CHCl3(g) - CC3(g) + HCl(g) 3) CC13(g) + Cl(g) → CCl4(g) 2 3 1 2 and 3 1 and 2

For the gas phase decomposition of dinitrogen pentoxide at 335 K, the rate of the reaction is determined by measuring the appearance of NO₂. 2 N₂O5 ⇒ 4NO₂ +0₂ At the beginning of the reaction, the concentration of NO₂ is 0 M. After 121 s the concentration has increased to 0.212 M What is the rate of the reaction? (mol NO₂/L) /s

Given the balanced equation: 2KCIO3 ---> 2KCI +30₂ Which type of chemical reaction does this chemical equation represent? A synthesis B single displacement C double displacement D) decomposition

Which choice is false in regards to solving for the molar mass of Na3PO4 (trisodium phosphate)? A The mass of one mole of Na3PO4 is 69.95 grams B The molar mass of Na3PO4 is 163.94 g/mol c The molar mass of Na is 22.99 g/mol x 3 D The molar mass of oxygen is 16.00 g/mol x 4

STP (standard temperature and pressure) is used as a reference point for the molar volume of an ideal gas. In the USA, most chemists, most general chemistry texts, and OWL use STP = 0°C, 1 atm, where the molar volume = 22.4 L/mol. If the reference pressure is chosen to be 1 bar, the molar volume is 22.7 L/mol. Do not confuse the two. A sample of carbon dioxide gas collected at STP occupies a volume of 21.7 L. How many moles of gas does the sample contain? ___mol

Write a net ionic equation for the reaction that occurs when potassium carbonate (aq) and excess hydroiodic acid are combined.

The compound nickel(II) nitrate is a strong electrolyte. Write the reaction when solid nickel(II) nitrate is put into water:

Which side is favoured, the reactants or the products? Explain how you know. Edit View Insert Format Tools Table

Iodine-131 is administered orally in the form of Nal(aq) as a treatment for thyroid cancer. What is the half-life of iodine-131 if 33.2 days are required for the activity of a sample of iodine-131 to fall to 5.71 percent of its original value? __ days

According to the kinetic molecular theory, liquid particles have greater Internal energy than gases less Internal energy than solids greater Internal energy than solids very strong Intermolecular forces

Balance the equation in basic conditions. Phases are optional. equation: CoCl₂ + Na₂O₂ Co(OH)3 + CI+Na+

Jolene was experimenting with a white-colored substance. She found that the substance as salt. Which of the following results could she have obtained? Negative for lodine test, positive for heat test, and negative for vinegar test. Negative for lodine test, negative for heat test, and negative for vinegar test. Positive for lodine test, positive for heat test, and negative for vinegar test. Positive for lodine test, positive for heat test, and positive for vinegar test.

For the reaction A + B -> C the rate law is determined to be rate = (0.25 M.s)[A][B]. Which of the following will increase the rate of the reaction? Please mark all that apply, and only those that apply. all of these will increase the rate. decreasing the temperature of the reaction increasing the concentration of reactant [A] increasing the concentration of reactant [B] increasing the concentration of product [C]

Methane gas (CH4) reacts with oxygen gas (0₂) according to the equation below: CH4 +20₂ → CO₂ + H₂O + energy This reaction releases 890 kJ of energy for every mole of methane consumed. Part 1. Is this reaction endothermic or exothermic? Part 2. What is the enthalpy change value for this reaction? Part 3. Explain in terms of potential energy, which has more energy -the products or the reactants. Explain your response.

At 37.5°C, the equilibrium constant for the reaction 2A(g) + B(g) ---> 2 C(g) is Kº=4.50 x 10-4. If the equilibrium concentrations of B and C are respectively 2.70 x 10-1 M and 4.75 x 10-3 M, the equilibrium concentration of A is a. 0.00431 M b. 0.215 M c. none of the other answers are correct d. 0.121 M e. 0.431 M

A first order reaction has a rate constant of 0.400 hr¹. What percent of reactant remains after 14.0 hours? a. 7.38 % b. 2.70 % C251 x 10-3% d. none of the other answers are correct e. 0.369 %

17.The concentration of CO₂ in a soft drink bottled with a partial pressure of CO2 of 6.5 atm over the liquid at 29 °C is 2.2 x 10¹ M. The Henry's law constant for CO₂ at this temperature is A) 2.2 x 10¹mol/L-atm B) 7.6 x 10-³ mol/L-atm C) 5.6 x 10-³ mol/L-atm D) 3.4 x 10-2mol/L-atm E) More information is needed to solve the problem.

Which of the following will increase the rate of a chemical reaction? Select all that apply. Increase concentration Decrease temperature Increase particle size Decrease concentration Catalyst Decrease particle size Increase temperature Use the following reaction progress diagram to answer questions 2-6.

The rate of a chemical reaction normally decreases as temperature increases. decreases as reactant concentration increases. increases as reactant concentration increases. is slowed down by a catalyst.

Which statement is NOT true about a reaction rate? Is the rate at which reactant is used up Increases with increasing temperature Is the speed at which product is formed All of the answers are true Increases with increase in reactant concentration

Consider the following elementary reaction: H₂(g) +2NO(g) N₂O(g) +H₂O(l) Suppose we let k stand for the rate constant of this reaction, and A. stand for the rate constant of the reverse reaction. Write an expression that gives the equilibrium concentration of H₂O in terms of k₁, k1, and the equilibrium concentrations of H₂, NO, and N₂O.

Nitric acid is a key industrial chemical, largely used to make fertilizers and explosives. The first step in its synthesis is the oxidation of ammonia. In this reaction, gaseous ammonia reacts with dioxygen gas to produce nitrogen monoxide gas and water. Suppose a chemical engineer studying a new catalyst for the oxidation of ammonia reaction finds that 597. liters per second of dioxygen are consumed when the reaction is run at 163. °C and the dioxygen is supplied at 0.53 atm. Calculate the rate at which nitrogen monoxide is being produced. Give your answer in kilograms per second. Round your answer to 2 significant digits.

Consider the following elementary reaction: NO₂(g) +F₂(g) NO₂F(g) + F(0) Suppose we let k stand for the rate constant of this reaction, and k1 stand for the rate constant of the reverse reaction. Write an expression that gives the equilibrium concentration of F in terms of k₁, k1, and the equilibrium concentrations of NO₂, F2, and NO₂ F.

Consider this reaction: 2SO3(g) → 2SO₂ (g) + O₂(g) At a certain temperature it obeys this rate law. rate = (48. M-¹.s¯¹) [SO3]2 Suppose a vessel contains SO3 at a concentration of 0.630M. Calculate the concentration of SO3 in the vessel 0.620 seconds later. You may assume no other reaction is important. Round your answer to 2 significant digits.

At a certain temperature this reaction follows second-order kinetics with a rate constant of 0.00913M-1s-1: H2CO3 (aq) → H2O (g)+CO2(aq) Suppose a vessel contains H₂CO3 at a concentration of 1.14 M. Calculate how long it takes for the concentration of H₂CO3 to decrease to 11.0% of its initial value. You may assume no other reaction is important. Round your answer to 2 significant digits.

The rate constant of a certain reaction is known to obey the Arrhenius equation, and to have an activation energy Ea = 63.0 kJ/mol. If the rate constant of this reaction is 6.6 M^-1 s^-1 at 129.0 °C, what will the rate constant be at 51.0 °C? Round your answer to 2 significant digits.

Under certain conditions the rate of this reaction is zero order in dinitrogen monoxide with a rate constant of 0.0075 Ms^-1: 2N₂O (g)→ 2N₂ (g) + O₂ (8) Suppose a 4.0 L flask is charged under these conditions with 500. mmol of dinitrogen monoxide. How much is left 4.0 s later? You may assume no other reaction is important. Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits.

A 50.0-mL sample of 0.90 M sodium hydroxide is quickly added to a calorimeter containing 50.0 mL of 0.90 M hydrochloric acid at 20.1°C. The equilibrium temperature of the reaction mixture is 26.7 °C. The reaction mixture weighs 99.85 g. HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O a. ΔT= _____ °C

The reaction between nitric oxide and oxygen is described by the following chemical equation: 2NO(g) + O₂ (g) 2NO₂ (g) Suppose a two-step mechanism is proposed for this reaction, beginning with this elementary reaction: NO (g) + O₂(g) → NO₂ (g) + O (g) Suppose also that the second step of the mechanism should be bimolecular. Suggest a reasonable second step. That is, write the balanced chemical equation of a bimolecular elementary reaction that would complete the proposed mechanism.