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Oxidation-Reduction and Electrochemistry

Redox Reactions, Oxidation Numbers, Limiting Reagent and Yield Problems

1. One of the steps in the commercial process of converting ammonia to nitric acid is the conversion of NH3 into NO: 4NH3(g) + 5O2(g) ---> 4NO(g) + 6H2O(g) In a certain experiment, 2.25 g of NH3 reacts with 3.75 g of O2. a) Which is the limiting reactant? b) How many grams of NO form? c) How many grams of the excess react

Dilution, Titration and Redox Problems

1. Draw me a beaker for each of the following 3 solutions. Show (label) the particles that exist when 1 particle of each dissolves. You don't have to show the water molecules! H3P04 C12H22011 HCHOO 2. Balance the following redox reaction that occurs in basic solution. NO2- (aq) + Al (s) ---> NH3 (g) + Al02- (aq) 3. Descr

oxidation number of the atoms

Determine the oxidation number for the indicated element in each of the following substances. S in SO2 C in COCl2 Mn in MnO4- Br in HBrO As in As4 O in K2O2 Im pretty lost on how to find them.

Electrode Potential and Gibbs Free Energy Problems

1. What is the standard electrode potential for the half reaction in which free ferric ion is reduced to elemental Iron? 2. Place the following chemical species in ascending order (in energetic terms) as electron acceptors under standard conditions. Fe3+ (reduced to Fe2+); Zn2+ (reduced to Zn); H+;Ag+;Cu2+ (reduced to Cu+)

Reaction Products from Aldehydes and Alcohols in Atmosphere

In air pollution chemistry and control, how is it that many common organic air pollutants such as methanol, formaldehyde, acetaldehyde, and phenol lose their oxygen ions and get converted ultimately to CO2 and H2O. For instance: CH3OH --> CH4 CH2O --> CO2 + H2O CH3CHO --> C2H4 C6H5OH --> C6H6 In each of these cases, wh

the weakest reducing agent

What criteria do you use to determine that an ion is the weakest reducing agent among several substances? Examine the following half-reactions and select the weakest reducing agent among the substances: Cr(OH)3(s) + 3e- <--> Cr(s) + 3OH-(aq) E= -1.48V SnO2(s) + 2H20(l) + 4e- <--> Sn(s) + 4OH

oxalate concentration for calcium oxalate to precipitate

7. The Ksp for calcium oxalate (CaC2O4) is 2.7 x 109. If the free Ca+2 concentration were 1mM, what would need to be the oxalate concentration for calcium oxalate to precipitate? 8. What would be the voltage of a Zn|Zn+2||Cu+2|Cu cell, once the concentration of Zn+2 went to 1.5M and the CU+2 concentration diminished to 0.5M?

Redox Reactions: Oxidation and Reduction

Can you please check this one: MnO4- + HSO3- (in acidic solution) Oxidation: MnO4- + 5e- + 8 H+ --> Mn2+ + 4 H2O Reduction: HSO3- + H2O --> SO42- + 2 e- + 3 H+ Balanced Equation: 2 MnO4- + 5 HSO3- + H+ --> 2 Mn2+ + 5 SO42- + 3 H2O I am having difficulty with these (especially, the ones in solution) Cyclohexanol + HO

IR Spectroscopy Puzzle

Explain how the information from the IR spectrum will be used to solve this puzzle. There are 2 puzzles; answer that question for each of them. See attached file for full problem description.

Haloform Reactions

The haloform reaction using I2 and NaOH is referred to as the "iodoform" test for methyl ketones. The test also gives positive results for compounds containing the -CH(OH)CH3 group. This results from the oxidation of the alcohol to the methyl ketone in the first stage. Write a balanced equation for the conversion of C6H5CHOHCH3

Quantitative Analysis of Metallic Iron

I put the penny in the silver nitrate solution for a half hour. The penny gives black precipitation and bubbles which come off the surface of the penny. My questions: 1. What is the gas that comes off the surface of the penny? (Hint: the half reactions that are going on between silver ions and copper) 2. Which is being red

Cell Potential and Reduction Potentials

Hi. Can someone please explain to me how to do the following question? I'm quite confused about how to do these. See attachment for better notation representation. Consider the following reaction at 25 degrees C, [Al3+] = 2.0 M and [Zn2+] = 1.0M 2 Al (s) + 3 Zn2+ (aq) -> 3 Zn (s) + 2 Al3+ (aq) a) Predict if the cell po

Exchange Current Density of Metal Ions

The following data were obtained for the reduction of metal ions A+ to metal A in a stirred solution at a 0.1 cm^2 electrode; the solution contained 0.01M A+. n(mV) -100 -120,-150, -180, -220, -280, -370, -500, -600 i(uA) -45.9, -62.6, -100, -170, -300, -510, -770, -965, -965 Calculate the exchange current density jo[uA/

Mendeleev and the periodic table

1. Why did Mendeleev leave three blank spaces in his periodic table? 2. Why do elements in a group of the periodic table have similar properties? 3. List five different metals give examples of how each metal is used. 4. List five different nonmetals. Give examples of how each nonmetal is used. 5. Why would you expect to find

Grignard reagent and synthesis of compounds

3. A novice chemist wishes to prepare 1-methyl-1,4-cyclohexanediol from the compound shown below (see attached). He wishes to use an appropriate Grignard reagent in the synthesis. Was the chemist successful? Explain why or why not. 4. Synthesize the following compounds using the indicated starting materials. a) Show TWO wa

Oxidation States of Iron and Color Differences

Both normal oxidation states of iron, Fe, will form low spin complex ions with cyanide (CN-); i.e., [Fe(CN)6]4 minus (aq) and [Fe(CN)6] 3 minus(aq). However the color of these ions is not the same. One ion is green-yellow (more yellow than green), which means it absorbs violet to blue light and the other is blood red in color,

Oxidation of Limonene

Limonene, C10H16, a terpene found in citrus peel, absorbs only two moles of hydrogen forming p-menthane C10H20. Oxidation by permanganate converts limonene into structure A in the attached .jpg (ignore structures B and C for this problem). 1. How many rings, if any, are in limonene? 2. What structures are consistent wit

Carbon Disulfide, CS2

Carbon Disulfide, CS2, is an important industrial substance. Its fumes can burn explosively in air to form sulfer dioxide and carbon dioxide. CF2(g) + O2(g) (arrow) SO2(g) + CO2(g) If 1.60 mol of CS2 burns with 5.60 mol of O2, how many mols of the excess reactant will still be present when the reaction is over.? Also .

Ice Cream Experiment

This experiment will introduce the concept of homogeneous, heterogeneous, mixtures, solutions, and the colligative property of freezing point. Materials 2 sandwich zip lock bags 2 one-gallon zip lock bags Thermometer 1 cup half-half or 2% milk 2 Tbs. (tablespoons) sugar 1/8 tsp. (teaspoon) flavoring {Choose from: v

Measuring oxygen release from reduction

If I had a lab where I had hydrogen peroxide which is reduced in the presence of a catalyst to oxygen and water, how can I measure the amount of oxygen that would be released?

Amount of energy required to purify copper using electrolysis?

The purification of copper by electrolysis involves an anode of impure copper and a cathode of pure copper. During the electrolysis, copper (II) ions leave the anode slab and plate onto the cathode slab. The reaction at the anode is Cu(s) = Cu2+(aq) +2e- The reaction at the cathode is Cu2+(aq) + 2e- = Cu(s) Therefore,

Solving for Delta G

Can you explain what we are doing mathematically, canceling, multiplying etc.? Thank-you. I am trying to understand how to balance this equation. We were given the following data to solve for delta G (standard). S(s) + 3/2 O2(g)--------->SO3(g) delta G standard = -371kJ 2SO2(g)+ O2(g)--------->2SO3(g) delta

Electrochemistry, redox reactions, and inorganic chemistry

4. A practical application problem which I have recently encountered: Recently while a stainless steel reactor vessel was being polished, a problem occurred with the workers' environment. While monitoring atmospheric composition while working in the vessel, high levels of carbon monoxide (above 100 parts per million) were det

Oxidation States of Elements

1. Identify oxidation states of all elements. 3Ag(s) + 4HNOsub3(aq)->3AgNOsub3(aq)+NO(g)+2H2O(l) I have everything except I thought O = -6 but it's wrong. Why? 2a)A 6.35L sample of gas is collected at 55degreeC and 0.892 atm. What volume of the occupy at 1.05 atm and 20.0degree C. PV=nRT (.892)(6.35)=n(o.o821)(55+2

Electrochemistry for Anodes and Cathodes

I am not sure if I have the right out come for this experiment for the following questions 1. Which one is the anode or the cathode? 2. What happens when the flame reaches the open end of the pipet. What property does this show about hydrogen gas? 3. What happens when turmeric indicator is added and connected to the power.

Molecular Structure -Lewis Diagrams

1. Write Lewis electron dot structures for (a) GeCI3-, (b) FC02- (c) CO32-, (d) AICI4-, and (e) FNO. Where more than one resonance structure is important, give examples of all major contributors. 2. Construct Lewis structures of typical resonance contributions of (a) ONC- and (b) NCO- and assign formal charges to each atom. W

Solving for Oxidation

Hi, I need assistance with the following two questions: 1)Determine the oxidation numbers for all elements in the reaction below: 6NaOH(aq) + 2Al(s) ----> 3Hsub2(g) + 2Nasub3AlOsub3(aq) b) Given 2.0g of solid Al in a cleaner, how much hydrogen gas will be produced? 2) Write the balanced molecular equation, complete

Determining Limiting Reagent

Given a solution containing 3.75 grams of PbCl2, you add enough Ru(OH)5 powder to completely use all of the PbCl2. What is the limiting reagent? 1) Complete and balance the reaction. Identify the state of each substance. 2) Identify the type of reaction. 3) Correctly name each reactant and each product. 4) Show the c