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General Chemistry

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

Ionics

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

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

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 polarity i. Isopropyl alcohol (ru

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

Balancing Chemical Equations and Finding Products

51. (a) The equations for two chemical reactions shown below are not balanced. Balance the equations by writing the appropriate coefficients in front of the formulas in the equations. (b) Write balanced equations for the chemical reactions described below. Writ the net ionic equation where appropriate. (i) A precipitate form

Calculations with Equilibrium

What copper (II) nitrate is dissolved in dilute hydrochloric acid the following is established. Cu(H2))6^2+(aq) + 4Cl-(aq) <---> CuCl4^2-(aq) +6H2O(l) (a) Write the equilibrium constant expression for this system. (b) Three test tubes are set up, each containing some of the equilibrium mixture. Each of the tubes is trea

Chemistry Solutions

1) An FM station broadcasts at 106.9 MHz, calculate the wavelength of the corresponding radio waves. 2) What is the amount of energy packaged in a photon with a wavelength of 310 nm ? 3) Calculate the frequency of EM radiation with a wavelength of 1.2 x 10-7 m 4) Write the full electronic configuration for Sr He

Thermodynamics, Gases, and Temperature

1- A radio station's channel, such as 100.7 FM or 92.3 FM, is actually its frequency in megahertz (MHz ), where 1MHz=10 6 Hz and 1Hz=1s −1 .Calculate the broadcast wavelength of the radio station 94.30 FM. 2- Hospital X-ray generators emit X-rays with wavelength of about 15.0 nanometers (nm ), where 1nm=10 −9 m . What is th

Calculate the Change in Enthalpy for the Reaction

1- Calculate the change in enthalpy for the reaction. (Use 1.0g/mL as the density of the solution and 4.18J/g⋅ ∘ C as the specific heat capacity.)? Instant cold packs, often used to ice athletic injuries on the field, contain ammonium nitrate and water separated by a thin plastic divider. When the divider is broken, the a

Solving various thermodynamics questions

1 - The air in an inflated balloon (defined as the system) is warmed over a toaster and absorbs 130J of heat. As it expands, it does 76kJ of work. What is the change in internal energy for the system? 2 - A piston has an external pressure of 8.00 atm. How much work has been done in joules if the cylinder goes from a volume o

Calculating the Mass of the Reaction and the Concentration

For the reaction shown, calculate how many moles of NO 2 form when each amount of reactant completely reacts. 2N 2 O 5 (g)→4NO 2 (g)+O 2 (g) 2.0mol N 2 O 5 6.4mol N 2 O 5 10.0g N 2 O 5 1.50kg N 2 O 5 For each reaction, calculate the mass (in grams) of the product formed when 10.1g of the underlined react

Calculating Delta H, S, and G

Use the data sheet to calculate Delta H, Delta S and Delta G at 25 degrees Celsius for each of the following reactions. In each case show that Delta G- Delta H-T Delta S. 1. Ni(s) + Cl2(g) --> NiCl2(s) 2. CaCO3(s, calcite) --> CaO(s) + CO2(g) 3. 2CH2OH(l) + 3O2(g) --> 2CO2(g) + 4H2O(l) Please see the attached docu