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    General Chemistry

    Radioactivity and Nuclear Chemistry Questions

    1. What is the correct name for the compound depicted in the skeletal structure below? (See attached file for diagrams) 2. Which of the following is a structural isomer of 2-methylpentane? Choose from: cyclohexane 2-methyloctane 2,2-dimethylbutane 3-ethylheptane n-butane 3. How many of the carbons in the molecule de

    Electrochemistry: Structures and Chirality

    1. What is the correct name for the compound depicted in the skeletal structure below? (see attachment) 2. Which of the following is a structural isomer of 3-ethylheptane? Choose from: 2-methylbutane cyclohexane 3,4-dimethylpentane 3-ethylnonane 4-methyloctane 3. How many of the carbons in the molecule depicted belo

    Problems on Electrochemistry

    Electrochemistry Part IV 1- When the following equation is correctly balanced in acidic solution, how many electrons are transferred? 2- What is the oxidation state of C in the CF4 molecule? 3- Which species is being reduced in the following reaction: 4- Calculate E°cell for the following redox reaction. Zn2+

    Electrochemistry and Balancing Redox Equations

    Electrochemistry Part III 1- Balance each redox reaction occurring in acidic aqueous solution. Express your answer as a chemical equation. Identify all of the phases in your answer. Ni(s)+Cd 2+ (aq)→Ni 2+ (aq)+Cd(s) Ni(s)+Cd 2+ (aq)→Ni 2+ (aq)+Cd(s) MnO 4 − (aq)+Al(s)→Mn 2+ (aq)+Al 3+ (aq) 2- Balance each r

    Electrochemistry: Numerical Problems

    1- What mass of Cu(s) is electroplated by running 28.5A of current through a Cu 2+ (aq) solution for 4.00 h ?Express your answer to three significant figures and include the appropriate units. 2-How many minutes will it take to electroplate 60.1g of gold by running 5.00 A of current through a solution of Au + (aq) ?Expre

    Electrochemistry- salt, voltaic cells and oxidation-reduction

    1. Why do cars rust quickly in cold climates where the roads are deiced by the spreading of salt? Choose from: The combination of low temperature and the presence of ions makes the redox reaction for forming rust more favorable. The salt acts as the cathode to complete the "cell." The salt promotes the formation of hydron

    Entropy Changes and Equilibrium states

    See Attachment for questions and Data CHM4 1- Calculate the standard entropy change for the reaction 2Na(s)+Cl 2 (g)→2NaCl(s) using the data from the following table: Substance ΔH ∘ f (kJ/mol) ΔG ∘ f (kJ/mol) S ∘ [J/(K⋅mol)] Na(s) 0.00 0.00 51.30 Cl 2 (g) 0.00 0.00 223.1 NaCl(s) -411.0 -

    Chemistry Change Questions

    1- Determine the sign of ΔS sys and ΔS surr for each chemical reaction.2CO(g)+O 2 (g)⇌2CO 2 (g)ΔH ∘ rxn = -566.0 kJ. Choose from: ΔS sys >0 , ΔS surr >0 ΔS sys <0 , ΔS surr >0 ΔS sys >0 , ΔS surr <0 ΔS sys <0 , ΔS surr <0 2-Determine the sign of ΔS sys and ΔS surr for each chemical reaction

    Chemical Reactions - Temperature and Gibbs Free Energy

    1- If ΔH = -60.0kJ and ΔS = -0.200kJ/K , the reaction is spontaneous below a certain temperature. Calculate that temperature. Express your answer numerically in kelvins. 2-The chemical reaction that causes aluminum to corrode in air is given by 4Al+3O 2 →2Al 2 O 3 in which ΔH rxn ∘ = −3352 kJ and ΔS rxn ∘

    Change in Gibbs

    1- Calculate the change in Gibbs free energy for each of the following sets of ΔH ∘ rxn , ΔS ∘ rxn , and T . Part A : ΔH ∘ rxn =− 122kJ ; ΔS ∘ rxn = 248J/K ; T= 298K Part B : ΔH ∘ rxn = 122kJ ; ΔS ∘ rxn =− 248J/K ; T= 298K Part C : ΔH ∘ rxn =− 122kJ ; ΔS ∘ rxn =− 248J/K ; T=

    Thermo Dynamics

    Given the values of ΔH ∘ rxn , ΔS ∘ rxn , and T below, determine ΔS univ . Part A: ΔH ∘ rxn = 80kJ , ΔS rxn = 143J/K , T= 299K Express your answer using two significant figures. Part B ΔH ∘ rxn = 80kJ , ΔS rxn = 143J/K , T= 754K Express your answer using two significant figures. Part C : ΔH

    Free Energy and Thermodynamics

    1-Consider the reaction: I 2 (g)+Cl 2 (g)⇌2ICl(g). K p = 81.9 at 25 ∘ C. Calculate ΔG rxn for the reaction at 25 ∘ C under each condition: Part A: standard conditions.Express your answer using one decimal place. Part B: at equilibrium Part C: P ICl = 2.55atm ; P I 2 = 0.315atm ; P Cl 2 = 0.219atm .Express your answ

    Buffer Solution and Entropy

    1-A 1.0-L buffer solution is 0.105M in HNO 2 and 0.145M in NaNO 2. Determine the concentrations of HNO 2 and NaNO 2 after addition of 1.4g NaOH .Express your answers using three significant figures separated by a comma. 2- A 1.0-L buffer solution is 0.105M in HNO 2 and 0.145M in NaNO 2. Determine the concentrations of HN

    Ionics: Buffer Solution, pH and Concentration

    1- Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution:a solution that is 0.165M in HC 2 H 3 O 2 and 0.120M in KC 2 H 3 O 2. Express your answer using two decimal places. 2- A buffer contains significant amounts of ammonia and ammonium chloride.Write an equation showing how this buffer

    Aqueous Metal Ions Accurate

    1) Why is it not very accurate to describe an aqueous metal ion as M+(aq)? Choose from: -because the metal ion is actually bound to several water molecules in a complex ion -because formation constants of complex ions tend to be very large, which makes the aqueous ions difficult to generate in solution -because a metal i

    Aqueous Ionic Equilibrium 2

    Aqueous Ionic Equilibrium 2 1- Which of the following processes will result in an increase of entropy of the system? Choose from: 2- What does the standard change in Gibbs free energy ( ) of a reaction tell us about the equilibrium constant (K) for that reaction under standard conditions? Choose from: There is

    Aqueous Ionic Equilibrium

    1- Consider the following titration curve of a weak acid titrated with strong base. At which point(s) on the graph is the solution a buffer? (see attachment for image) 2- Which of the following solutions has the highest buffer capacity? Choose from: 0.100 M NaCl / 0.100 M NaOH pure H2O 0.050 M NaCN / 0.050 M HCN 0.100 M

    Brønsted-Lowry Concept of Acids and Bases

    Chapter 15 (Acids and Bases) Questions Part 2 1- 0.25g of sodium hydroxide (NaOH ) pellets are dissolved in water to make 7.0L of solution. What is the pOH of the solution in Part B? Express the pOH numerically to two decimal places. 2- Calculate the pH of a 0.10 M solution of barium hydroxide, Ba(OH) 2 .Express your answer nu

    Questions on Acids and Bases

    1- What is the difference between a strong acid and a weak acid? Choose from: A strong acid is dangerous to human health, a weak acid is not. A strong acid dissociates completely in solution, while a weak acid only dissociates partway. A strong acid will neutralize a base, but a weak acid isn't strong enough to do so. A w

    CHM Kenetics

    1-A student performs a kinetics experiment in which they measure the time it takes for a reaction to proceed using a color change for indication. They vary concentrations of one reactant to determine the order of the reaction relative to that reactant. They compare their measured reaction rates to their classmates and discover t

    Kinetics and Rate of Reactions

    1. To measure the speed of a car, we use miles per hour (miles/hour or mph ). To measure the rate of a reaction we use molar concentration per second (M/s ). Part B: What is the average rate of formation of Br 2 = 0.030 M/s Part C: Based on your answer to Part B, what is the average rate of formation of HCl ? Express your ans

    Chemical Kinetics: Assessing Reactions

    See the attached file. 1. Now consider the following reaction and data: H 2 +2BrCl→2HCl+Br 2 Time (s) Br 2 concentration (M) 5 1.35 15 1.65 Part A What is the average rate of formation of Br 2 ?Express your answer to three decimal places and include the appropriate units. 2. Consider the reaction: A(g)+1 2 B(

    Chemical Kenetics

    Chemical Kenetics 1- Consider the following elementary steps that make up the mechanism of a certain reaction1 1. 3A→B+C 2. B+2D→C+F 2- What is the rate law for step 1 of this reaction? Express your answer in standard MasteringChemistry notation. For example, if the rate law is k[A][C] 3 type k*[A]*[C]^3. 3- W

    Solve: Chemical Equilibrium

    Chemical equilibrium 2 1- Carbonyl fluoride, COF 2 , is an important intermediate used in the production of fluorine-containing compounds. For instance, it is used to make the refrigerant carbon tetrafluoride, CF 4 via the reaction 2COF 2 (g)⇌CO 2 (g)+CF 4 (g), K c =5.60 If only COF 2 is present initially at a concentratio

    Chemistry: Chemical Equilibrium

    Chemical Equilibrium 1- Determine the value of the equilibrium constant, K goal , for the reaction N 2 (g)+H 2 O(g)⇌NO(g)+ 1 2 N 2 H 4 (g) , K goal =? by making use of the following information: 1.N 2 (g)+O 2 (g)⇌2NO(g) , K 1 = 4.10×10 −31 2.N 2 (g)+2H 2 (g)⇌N 2 H 4 (g) , K 2 = 7.40×10 −26 3.2H 2

    Solute and Solvent

    In the background information, the table showed you that a mixture can be made between a minimum of two solids (SS), two liquids (LL), two gases (GG), gas and liquid(GL), solid and gas (GS), solid and liquid (SL). You will make mixtures that have some of the components mentioned above. Big picture: The purpose of this experimen

    Paper Chromatography

    See the attached file. Experimental Procedure 1. Obtain the following items: a. 600 ml Beaker b. A no. 2 lead pencil with a sharp point c. A ruler graduated in centimeters d. 2 sheets of 20lb. white copy paper e. Food dyes (food coloring) i. Red ii. Blue iii. Yellow iv. Green f. Eluting solvents of varying polarit

    Electrons Table

    Chapter 8 1- What is a likely source of error in identifying a compound using thin layer chromatography? Choose from: not accurately measuring the volume, the time, mass, distance or density 2- What property is used to separate solutes using thin layer chromatography? 3- Consider the following image, in which the 'x' design

    Boiling Point, Vaporization and Electronic Configuration

    1. Place these hydrocarbons in order of decreasing boiling point (see attached file for formulas) 2. What is the normal boiling point of this compound? (see attached file for formula) 3. The constants for H2O are shown in the attachment. Part A How much heat energy, in kilojoules, is required to convert 80.0g of ice at