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Physical Chemistry

Ionic strength

Question 1 Determine the ionic strength, μ, for each of the following solutions. Assume complete dissociation of each salt and ignore any hydrolysis reactions. a) A solution of 0.00556 M FeSO3 b) A solution of 0.00282 M CuCl2 c) A solution of 0.000853 M CaBr2 and 0.000509 M La(NO3)3 Question 2 Part 1 What happens t

Analyzing Oxidation States

I am confused about the Oxidation States table (see attached file). Here is the experiment that I have to do. - Gather five clean test tubes and place them side by side - Place 5mL of water in the first tube - Place 5mL of KMnO4 in the second tube - Place 2mL of KMnO4 in to tubes 3, 4, and 5 - Place 1mL of NaOH in tube 3

Vaporization of Water

1. Calculate Q,W and delta U for the conversion of 1 mole of liquid water to steam at T = 100C and P = 1 atm. The heat of vaporization of water is 9720 cal/mol. 2. From the result of problem 1, estimate the approximate energy in one mole of hydrogen bonds. Explain your reasoning. 3. Determine delta H for the partial comb

Calculating Rate and Activation Energy of Diffusion

a) How do I calculate the time that will it take for 0.001 moles of CO2 to leak from a container at steady-state, assuming that the amount of CO in the surroundings is insignificant? b) If the diffusivity is observed to double when the temperature is increased by 10 degrees C, how do I calculate the activation energy for diff

Polyethylene Density

(a) Which is the higher density of polyethylene, linear or branched? Select the choice with the best accompanying explanation. (b) High-density polyethylene (HDPE) is opaque (white) while low-density polyethylene (LDPE) is transparent to visible light. Select the best explanation for this observation.

Thermochemistry and Periodic Properties of Elements

1. State which atom is larger according to periodic trends. Explain the difference for each of the pairs. a) Br, F b) Ca, Mg c) C, Si d) He, Ar 2. State which atom has a smaller first ionization energy according to periodic trends. Explain the difference in ionization energy for the pairs. a) O, S b) K, Na c) Cd, Zn d

Acid Mixture Problem

From a full 50-liter container of a 40% concentration of acid, x liters is removed and replaced with a 100% acid. a) Write the amount of acid in the final mixture as a function of x b) Determine the domain and range of the function c) Determine x if the final mixture is 50% acid

Net Ionic Equations and Balancing

I'm not sure what it is about this stuff that confuses me but I can't seem to get this stuff to stick. Detailed work would be kindly appreciated. Write balanced molecular, ionic and net ionic equations for the following: 1. Mg(OH)2 (aq) + HCL (aq) --> MgCl2 (aq) + H20 (l) 2. K2(C2O4) (aq) + CaCl2 (aq) --> KCL (aq) CA(C2O4)

Standard Temperature and Pressure of Chlorine

Chlorine is widely used to purify municipal water supplies and to treat swimming pool waters. Suppose that the volume of a particular sample of Cl2 gas is 8.70 L at 895 torr and 240C. 1) How many grams of chlorine are in the sample? 2) What volume will the chlorine occupy at Standard Temperature and Pressure (STP)? 3) At wh

Chemistry: Reaction between Sodium Bicarbonate and Citric Acid

Question: The fizz produced when an Alka Seltzer© tablet is dissolved in water is due to the reaction between sodium bicarbonate and citric acid, according to the following equation: 3NaHCO3(aq) + H3C6H5O7(aq) -> 3CO2(g) + 3H2O(l) + Na3C6H5O7(aq) In a certain experiment, 1.00 g of sodium bicarbonate and 1.00 g citric acid a

Combustion Analysis of Toluene

Combustion analysis of toluene, a compound containing carbon and hydrogen only, gives 5.86 mg carbon dioxide and 1.37 mg of water. What is its empirical formula? Menthol is composed of carbon, hydrogen and oxygen. A 1.005 g sample is combusted, producing 0.2829 g carbon dioxide and 0.1159 g of water. If the molar mass of ment

Reaction Rates: Solid State Chemistry

Hi, please refer to the attachment to view the graph. Questions: - What is the order of the reaction? - What is the reaction rate constant? - How will the graph shown change if a catalyst is added to the system? - How will the graphic shown change as the temperature of the system varies? It will be greatly appreciated

Change in Temperature in the Production of Silver Chloride

When solutions containing silver ions and chloride ions are mixed, silver chloride precipitates: Ag+(aq) + Cl-(aq) ?AgCl(s) deltaH = -65.5 kJ Calculate deltaH for the production of 0.200 mol of AgCl by this reaction. Calculate deltaH for the production of 2.50 g of AgCl. Calculate deltaH when 1.500 mmol of AgCl dissolves

Solid States, Half Lives and Young's Modulus Questions

1.) (A) DEFECTS Metals yield at a stress much lower than those calculated on the basis of their bond strength alone. This is explained by the presence of defects. Identify the principal defects responsible for this observation. a.) Grain Boundaries b.) Interstitial Metal Atoms c.) Vacancies d.) Dislocations 1.) (B) DEF

Stoichiometry Help Needed

I once again am stuck on some problems in this chapter. While there is many more I don't get these six I think would help me with the others I'm stuck on. Would highly appreciate very detailed work shown so I can understand the process and apply to other questions of like nature. 1. Using the the following equation: 2 NAOH +

Chemical Reactions and Stoichiometry Problems

Please assist with answering the following questions. I'd love to be able to see a step to step process for solving these, that way when I come across problems similar to this in the future and then, I don't get lost again. 1. 2Mn02 + 4KOH + O2 + CL2 ---> 2KMnO4 + 2KCL + 2H2O For the reaction above, there is 100.0 g of each

Solid State Chemistry - Density, Absorption, Charge

1.) FREE CARRIER DENSITY Chemical analysis of a germanium crystal reveals indium at a level of 0.0003091 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Ge matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in this Ge crystal? 2.) BORON DOPING D

Chemistry Reaction: 2LiOH + CO2 -> Li2CO3 + H2O

Is the following equation balanced? 2LiOH + CO2 -> Li2CO3 + H2O 1- Determine the number of atoms for each element in the reactants. 2- Determine the number of atoms for each element in the products. 3- Given this determination, is the reaction balanced? 4- If the reaction is not balanced, what is the balanced che

Calculating Rate Constant using Hard-Sphere Theory

I have a problem I am unable to figure out, I keep using the hard-theory formula for "A" to get the rate constant, however the value I get seems way to small every time I try to do it. Can someone please help me with this problem? I posting the homework set its problem number 5, I keep getting (4.28x10^-29dm3/mol s) as "k" pleas

Calculating Delta Hf for CaC2

Calcium carbide reacts with water to form acetylene and calcium hydroxide. From the following enthalpy data calculate Delta Hf for CaC2 DeltaHf H2O=-285.83 kj/mol DeltaHf Ca (OH)2=-986.2 kj/mol DeltaHfC2H2=226.77 kj/mol Please provide a detailed explanation.

Balanced Thermochemical Equation and Enthalpy Diagram

The decomposition of zinc carbonate, ZnCO3(s), into zinc oxide, ZnO(s), and CO2(g) at a constant pressure requires the addition of 71.5kJ of heat per mole of ZnCO3. Write a balanced thermochemical equation for the reaction and draw an enthalpy diagram for the reaction, showing the activation energy, Ea, and the enthalpy chan

Calculating Standard Enthalpy Change, Heat, & Mass of a Reaction

Methanol (CH3OH) is used as fuel in race cars. Calculate the standard enthalpy change for the reaction, assuming H2O(g) as a product. Calculate the heat produced by combustion per liter of methanol. Methanol has a density of 0.791g/ml. Calculate the mass of CO2 produced per kJ of heat emitted.

Electrochemistry and Solubility

Please provide some assistance on understanding how to get the half reactions (balanced) all the way to the solubility for the question below, using the nernst equation and solubility equation. I would greatly appreciate it. The part that I really have no clue how to get is the solubility of Bi2S3 so if you would like, please ju

Solid State Chemistry Questions

Hello. I need some help with the following. Can you please help? Please check the file attached. 1.) Of the molecules below, select those that are paramagnetic. It may be useful to draw a molecular orbital energy diagram and to fill in the electrons for each molecule. Li2 B2 N2 CN− O−2 O2−2 2.) Give the bond ord

Chemistry: Compounds in Equilibrium

Compounds A and B are in equilibrium. For the reaction A --> B, E_s is 15 kcal/mol (62.8 kj/mol) and delta H in degrees is 12 kcal/mol (50.2 kj/mol). Draw a reaction profile diagram for this equilibrium. What are the E_s and delta H in degrees values for the reaction B --> A? What are the percentages of A and B in the reaction m

Aluminum hydroxide and sulfuric acid reaction

Aluminum hydroxide reacts with sulfuric acid as follows: 2 Al(OH)3 (s) + 3 H2SO4 (aq) ---> Al2(SO4)3 (aq) + 6 H2O (l) (a) Which reagent is the limiting reactant when 0.450 mol Al(OH)3 and 0.550 mol H2SO4 are allowed to react? How many moles of the excess reactant remain after the completion of the reaction? Please explain in

Calculating percent by mass

A 1.248 g sample of limestone rock is pulverized and then treated with 30.00 mL of 1.035 M HCl solution. The excess acid then requires 11.56 mL of 1.010 M NaOH for neutralization. Calculate the percent by mass of calcium carbonate in the rock, assuming that it is the only substance reacting with the HCl solution. Please ex

Chemistry Concentrations

In each of the following pairs, indicate which has the higher concentration of Cl- ion: 0.10 M CaCl2 or 0.15 M KCl solution, 100ml of 0.10 M KCL SOLUTION OR 400 ML OF 0.080M LiCl solution, 0.050 M HCL solution or 0.020 M CdCl2 solution Please provide a detailed explanation.

The Chemistry of Nicotine

Nicotine, a component of tobacco, is composed of C, H, and N. A 5.250-mg sample of nicotine was combusted producing 14.242 mg of CO2 and 4.083 mg of H2O. What is the empirical formula for nicotine? If the substance has a molar mass of 160 ± 5 g/mol, what is its molecular formula? Please convert from mg to g.

Empirical Formula of a Compound and Conversion

The characteristic odor of pineapple is due to ethyl butyrate, a compound containing carbon, hydrogen, and oxygen. Combustion of 2.78 mg of ethyl butyrate produces 6.32 mg of CO2, and 2.58 mg of H2O. What is the empirical formula of the compound? Please convert from mg to g.