Joe Gifford in Tal Afar, Iraq

Explain how  the rate of reaction rate in pressure cookers was increased by including these subtopics: 1.  Explain with collision theory and energy potential diagrams: how the rate of reaction is affected by temperature, surface area, nature of reactants, concentration, etc. by using collision theory? 2l Discuss whether the reaction is endothermic or exothermic (use Hess’s Law, Le Châtelier’s Principle, or Kinetic Molecular Theory to explain in increasing rate of reaction and relevance by including all 4 required subtopics )

REIFUNG DISTING Pressure (atm) 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 0 A B 5 10 15 ● · ● 20 25 Time (minutes) 30 35 C D 40 45 00 50

Chlorine atoms in the atmosphere can react with ozone. Mathematically combine the following two reactions to create an overall balanced equation with the lowest whole-number coefficients. All chemical species in the reaction are gas-phase. Which of the following best represents the overall reaction? C1+03 → Clo+0₂ c10+ 0 → Cl + 0₂ To combine the reactions to create the overall balanced equation, you need to eliminate spectator species and only include the remaining species. O There are two lone chlorine atoms in the overall balanced reaction. O Two chlorine atoms can cause the production of two oxygen molecules. O CIO appears on the reactant and product side of the overall balanced reaction. Lone oxygen atoms are consumed by the overall reaction. O There is a net conversion of O2 to 03.

B. Rates of reaction are typically measured as the change of concentration per unit time. Some typical units of concentration are: M, mM, pM, µM, nM. Some typical units of time are: years, days, hr, s, ms, ps, µs, and ns. For each reaction, suggest a reasonable unit of measure for the rate of reaction. a. The combustion of gasoline. b. The transformation of organic material into crude oil. Chemical change involved with memory in the human brain. с. d. The rusting of an iron nail. 9. Why would a scientist use nM/ps instead of M/s? - 112 -

How Long it Might Take for PFOA Blood Levels to Decline Assumes a 3-year half-life (Micrograms per Liter) 100 Average PFOA Levels in Blood (Micrograms per Liter) 3M Workers, Decatur, AL 1,125 This figure estimates a 3-year half-life of PFOA levels in blood at different starting levels of exposure. PFOA levels decrease by about half every two to four years. 90 Dupont Workers, Parkersburg. WV 410 80 C8 Study: Little Hocking. OH 228 A half-life is the amount of time it takes C8 Study: Lubeck, wV 92 for PFOA levels in blood to be reduced 70 by half. C8 Study: Tuppers Plains, OH 42 * The level shown for PFOA in blood for the Hoosick Falls area is the geometric mean and is based on test results for 2,081 participants including people using Village water, people using private wells, people who work in the area, and former residents. 60 Hoosick Falls area, NY I 23.5* C8 Study: Mason County, WV I 16 50 U.S. Population Geometric means are a way of calculating the middle level. They are used in…

Scientists can determine the age of ancient objects by the method of radiocarbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope of carbon, 14C, with a half-life of about 5,730 years. Vegetation absorbs carbon dioxide through the atmosphere, and animal life assimilates 14C through food chains. When a plant or animal dies, it stops replacing its carbon, and the amount of 14C present begins to decrease through radioactive decay. Therefore, the level of radioactivity must also decay exponentially. Dinosaur fossils are too old to be reliably dated using carbon-14. Suppose we had a 66 million year old dinosaur fossil. What percent of the living dinosaur's 14C would be remaining today? (Round your answer to five decimal places.) 0.0000007537 X % Suppose the minimum detectable amount is 0.2%. What is the maximum age (in years) of a fossil that we could date using 14C? (Round your answer to the nearest year.) yr

Scientists can determine the age of ancient objects by the method of radiocarbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope of carbon, 14C, with a half-life of about 5,730 years. Vegetation absorbs carbon dioxide through the atmosphere, and animal life assimilates 14C through food chains. When a plant or animal dies, it stops replacing its carbon, and the amount of 14C present begins to decrease through radioactive decay. Therefore, the level of radioactivity must also decay exponentially.   a) Dinosaur fossils are too old to be reliably dated using carbon-14. Suppose we had a 67 million year old dinosaur fossil. What percent of the living dinosaur's 14C would be remaining today? (Round your answer to five decimal places.)   b) Suppose the minimum detectable amount is 0.7%. What is the maximum age (in years) of a fossil that we could date using 14C? (Round your answer to the nearest year.)

Scientists can determine the age of ancient objects by the method of radiocarbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope of carbon, 14C, with a half-life of about 5,730 years. Vegetation absorbs carbon dioxide through the atmosphere, and animal life assimilates 14C through food chains. When a plant or animal dies, it stops replacing its carbon, and the amount of 14C present begins to decrease through radioactive decay. Therefore, the level of radioactivity must also decay exponentially. Dinosaur fossils are often dated by using an element other than carbon, like potassium-40, that has a longer half-life (in this case, approximately 1.25 billion years). Suppose the minimum detectable mass is 0.4% and a dinosaur is dated with 40K to be 67 million years old. Is such a dating possible? What is the maximum age (in millions of years) of a fossil that could be dated using 40K? (Round your answer to one decimal place.) (Can you…

Step 1: (slow) Step 2: (fast) = CI The particle models shown above represent a proposed two-step mechanism for the destruction of ozone (O3) in the upper atmosphere. Based on the proposed mechanism, what is the balanced chemical equation for the overall reaction? A O3 (9) + Cl(g) O2(g) + CIO(g) B 2 03(g) + 2 Cl(g) → 2 O2(9) + 2 C1O(g) C) O3(g) + CI(g) + Cl0 (g) → 2 O2(9) + Cl2 (9) 2 03(9) 3 02 (g)

The rate of a certain reaction is given by the following rate law: rate= te k[N₂] [H.] Use this information to answer the question below. The rate of the reaction is measured to be 2.0 -1 k= x 10¹ M/s when [N₂1 = 0.034 M and [H₂] = 1.6 M. Calculate the value of the rate. constant. Be sure your answer has the correct number of significant digits. X

(#28) Reaction Rates and time. A decomposition reaction in the first order has a rate constant of 1.26 x 10-4/sec. If the initial concentration of the reactant is 0.644 M. how much time will it take before 20% of the reactant has decomposed? 28a) In blank #1, type-in the working formula to solve for the time required. Enter the algebraic formula as a one-line equation and without spaces in between characters. Use lowercase for all fonts. 28b) In blank #2, type in your answer for the time it will take for 20% f the reactant to decompose. The answer is in seconds but do not include the unit. Enter your answer as a whole number with four significant figures.

What is the role of carbon dioxide in air in Fresco Painting? What type of catalytic mechanism (heterogenous or homogenous) exist in Fresco painting? Why?

There is concern that synthetic bromine-containing compounds, in addition to chlorofluorocarbons, are helping to destroy ozone in the stratosphere. The Bro [see part (g)] can take part with ClO in the following catalytic cycle: Cl + O3 → ClO + O, Br + O3 → BrO + O, CIO + BrO → Cl + Br + O2 Write the overall equation for this cycle.

Calculate the full rate law using the information below: 2 NACHOS (g)  →  12 CHIPS (g)  +  3 CHEESE (g)   [NACHOS]0 (M)                   Initial Rate (M–1s–1) 0.101                                     0.00484 0.0910                                   0.00437 Group of answer choices Rate  =  5.61 × 10–2 M–1 s–1 [NACHOS]2 Rate  =  6.03 × 10–1 M–2 s–1 [NACHOS]3 Rate  =  4.79 × 10–2 s–1 [NACHOS] Rate  =  1.66 × 10–3 M1/2 s–1 [NACHOS]2/3 Rate  =  1.78 × 10–2 M–1/2 s–1 [NACHOS]3/2

Reaction 1 FeO(s) + CO(g) → Fe(1) + CO2(g) AG" > 0 Reaction 2: C(s) + CO2(g) → 2 CO(g) AGzn <0 Overall reaction: FeO(s) + C(s) → Fe(l) + CO(g) AG n < 0 Subm The chemical equations above represent the main reactions that occur during the production of Fe(l) under certain conditions. The overall reaction couples reactions 1 and 2, resulting in a < 0? thermodynamically favorable process. Which of the following best explains whether or not a particle diagram could represent how the coupling of reaction 1 and reaction 2 results in AG A particle diagram that represents the increase in the volume of gaseous product particles would be a good representation of how the coupling of reactions 1 and 2 results in a thermodynamically favorable process. A particle diagram that represents the decrease in the average kinetic energy of the particles would be a good representation of how the coupling of reactions 1 and 2 results in a thermodynamically favorable process. A particle diagram cannot represent…

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Determine whether the following statements are true or false, and explain your answer in one sentence. a) The rate law for an overall reaction 2A (g) -> B (g) is: Rate = k[A]^2 b) The rate law for an elementary step 2A (g) -> B (g) is: Rate = k[A]^2 c) The rate of an overal reaction is the rate of the slowest elementary step within its mechanism.