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The contractor calls for glass elements that measure 4.519 x 13.746 meters. If the average temperature in the area is 12.5 degrees celsius and the glass will be exposed to a temperature range of -23 degrees Celsius to 48 degrees Celsius, by how much will be the glass surface area fluctuate?

Classify the following organic reaction below

The new housing development is located 3 miles from a smokestack and exposed to 1.4 x 10^-4 mg/m³ of benzene.

a. Determine the carcinogenic risk for a 50 kg adult who breathes the air at 0.25 m³/hr for 8 hours a day over a period of 10 years.

b. Is the risk acceptable if we consider 1 in a million acceptable?

What is the packing of the S atoms in the ZnS lattice and where are the Zn atoms?

The Ksp of Al(OH)₃ is 2 x 10^-32. At what pH will a 0.8 M Al³⁺ solution begin to show precipitation of Al(OH)₃?
A) 10.5
B) 6.0
C) 3.5
D) 3.0
E) 1.0

Which processes are important for determining the vapor pressure of a liquid? Select all that are True.

melting

freezing

condensation

vaporization

sublimation

Which of the following statements is true?

A. The surface tension of a liquid is generally independent of temperature.

B. The viscosity of a liquid is generally independent of temperature.

C. Gases are not fluids.

D. Volatile liquids have high vapor pressures.

Combustion analysis of a compound known to contain just C, H, N, and O demonstrated that it is 46.21 wt% C, 9.02 wt % H,13.74 wt% N, and, by difference, 100 - 46.21 - 9.0213.74 = 31.03 wt% O. This means that 100 g of the unknown would contain 46.21 g of C, 9.02 g of H, and so on. Find the atomic ratio C:H:N:O and express it as the lowest reasonable integer ratio.

Explain how the ratio of ions in the formula is linked to the charge on the ions

 A chef finds a sealed container consisting of an ingredient that goes into his restaurant’s secret sauce. The ingredient’s molecules are moving in place. What will happen if the chef causes the ingredient to change phase by transferring energy into it?

Oxygen tank is necessary for mountain climbing. A person purchased a 5L oxygen tank in a store at the bottom of a mountain (i.e., room temperature is 25⁰C). When he/she climbs to the top of the mountain, 60% of the oxygen in the tank is used. Please determined the pressure decrease (in percentage) if the temperature at the top of the mountain is -10⁰C.

The right side of an open-ended manometer was connected to a sample of gas while the left side was open to the atmosphere. The difference in height of the liquid in the manometer was recorded as 102 mm, with the height of the liquid higher on the right side of the manometer. Determine the pressure (in atm) of the gas given that the atmospheric pressure was measured to be 0.994 atm.  

The equilibrium constant, K, for the following reaction is 1.80×10^-2 at 698 K.

An equilibrium mixture of the three gases in a 1.00 L flask at 698 K contains 0.325 M HI, 4.36×10^-2 M H_2, and 4.36×10^-2 M I₂. What will be the concentrations of the three gases once equilibrium has been reestablished, if 0.244 mol of HI(g) is added to the flask?

When HNO₃ (flask) is titrated with KOH (burette), which response best describes the equivalence point? 

a. The pH = 7 since it has the same moles of acid and base present.

b. The pH > 7 since the conjugate base would be present.

c. The pH > 7 since there is a strong base present.

d. The pH < 7 since the conjugate acid would be present.

e. The pH < 7 since there is a strong acid present.

How to solve the question further?? And please tell stepwise that how to solve the term with power 3/2.

The specific heat capacity of a pure substance can be found by dividing the heat needed to change the temperature of a sample of the substance by the mass of the sample and by the change in temperature. The heat capacity of a certain substance has been measured to be 4.88J·g°C. Suppose 175.g of the substance are heated until the temperature of the sample has changed by 7.85°C. Write an equation that will let you calculate the heat Q that was needed for this temperature change. Your equation should contain only symbols. Be sure you define each symbol.

If 2.50 g of CuSO₄ are dissolved in 6.0 × 10² mL of 0.45 M NH₃ solution, what are the concentrations of Cu²⁺, Cu(NH₃)₄²⁺, and NH₃ at equilibrium? The formation constant for Cu(NH₃)₄²⁺ is 5.0 × 10¹³. 

In November 1987, a massive iceberg broke loose from the Antarctic ice mass and floated free in the open ocean. The chunk of ice was estimated to be 98 mi long, 25 mi wide, and 750 ft thick. A typical backyard swimming pool contains about 24,000 gallons of water. How many of these pools could you fill from the water in this iceberg? 

A student prepared a stock solution by dissolving 15.0 g of KOH in enough water to make 150 mL of solution. She then took 15.0 mL of the stock solution and diluted it with enough water to make 65.0 mL of a final solution. What is the concentration of KOH for the final solution?

A quantity of HI was sealed in a tube, heated to 425 °C, and held at this temperature until equilibrium was reached. The concentration in the tube at equilibrium was found to be 0.0706 mol/L for HI, and 0.00955 mol/L for H₂ and for I₂. Calculate the K_eq for the gas-phase reaction

TThe air pollutant NO is produced in automobile engines from the high-temperature reaction:

at 2300 K

If the initial concentrations of N₂ and O₂ at 2300 K are 2.24 M and 0.56 M, respectively, what are the concentrations of NO, N₂, O₂ when the reaction mixture reaches equilibrium?

A student placed 12.5 g of glucose (C₆H₁₂O₆) in a volumetric flask, added enough water to dissolve the glucose by swirling, then carefully added additional water until the 100. mL mark on the neck of the flask was reached. The flask was then shaken until the solution was uniform. A 45.0 mL sample of this glucose solution was diluted to 0.500 L. How many grams of glucose are in 100. mL of the final solution?

The compound strychnine is a deadly poison used to kill rats and other rodents. It is also fatal to humans so don’t snack on it! It has a molecular mass of 334 g/mol. A 5-gram sample was found to contain 3.77 grams of C, 0.48 grams of O, 0.42 grams of N, with the rest being hydrogen. Calculate the empirical formula for strychnine.

A container has a mixture of NO₂ gas and N₂O₄ gas in equilibrium. The chemical reaction between the two gases is described by the equation

The partial pressure of NO₂ is 61.2 MPa and the partial pressure of N₂O₄ is 38.8 MPa. Several weights are added to the lid of the container, increasing the total pressure on the container to 200 MPa. What are the most likely partial pressures when equilibrium is established again?

A 4.60 mol sample of solid A was placed in a sealed 1.00 L container and allowed to decompose into gaseous B and C. The concentration of B steadily increased until it reached 1.10 M, where it remained constant.

Then, the container volume was doubled and equilibrium was re‑established. How many moles of A remain?

The absorbance of a solution of NiCl₂ Of unknown concentration is found to be 0.388. What is the concentration of this solution?

A spectrophotometer has a meter that gives a reading directly proportional to the amount of light reaching the detector. When the light source is off, the reading is zero. With the pure solvent in the light path, the meter reading is 78; with a 0.1 M solution of a solute in the same solvent, the meter reading is 55. The light path is 0.5 cm. Calculate the absorbance, the transmittance, and the molar absorption coefficient.

Background information: Collected hydrogen and oxygen gas in collection bulbs (pipets) and lit it up with a match to see which ratio (e.g., 2 parts H, 4 parts O; 1 part O and 5 parts H) will provide the loudest "pop" sound

Why do hydrogen and oxygen gas mixtures in a collection bulb not react as soon as they are collected? (Note: Take into consideration the role of the match and the properties of gas molecules at room temperature)

Which statement describes the reaction shown below under standard pressure conditions at 25 ºC?

A. Spontaneous forward

B. Spontaneous reverse

C. At Equilibrium

ΔGº = -70.54 kJ

ΔHº = -114.14 kJ

ΔSº = -146.43 J/K

At what temperature (in ºC) will the reaction change the direction in which it is spontaneous under standard pressure conditions?

Calculate the solubility of Ca(OH)₂ in a 0.570M NaOH solution at 31 °C, given that the Ksp of Ca(OH)2 is 4.96 x 10^-6 at that temperature.
Give your answer in micro Molar units

What is the molarity of a potassium triiodide solution, KI₃(aq), if 30.00 mL of the solution is required to completely react with 25.00 mL of a 0.500 M thiosulfate solution, K₂S₂O₃(aq)?

The chemical equation for the reaction is

3. Which of the following electron transitions corresponds to emission of the longest wavelength light?

A. from n = 3 to n = 2

B. from n = 1 to n = 5

C. from n = 4 to n = 2

D. from n = 1 to n = 2

E. from n = 5 to n = 1

4. Emission from an excited Hg atom emits at 254 nm. What is the frequency of this light?

A: 1.18e15 sec^-1

B: 1.18e15 sec

C: 1.18e6 sec^-1

D: 1.18e6 sec

Use Delta H* and Deta S standard to calculate the normal boiling point of carbon tetrachloride in C*

1. Consider the following reaction at 25 °C

Calculate Keq for the above reaction at 25 °C.

Q1. Which of the following processes are spontaneous and which are non spontaneous.
a) The combustion of natural gas
b) Extraction of Aluminum metal from its ore
c) A ball rolling down a hill
d) A bike going up a hill

Q2. Predict the entropy change (positive or negative) for the following processes/reactions
a) a lake freezing
b) weeding a garden
c) N2(g) + 2 H2(g) ? N2H4 (g)
d) Mg(s) + 2H2O(l) ? Mg(OH)2 (s) + H2(g)

Q3. The element Cesium (Cs) freezes at 28.4 C and its molar enthalpy of fusion ΔH_fusion = 2.09 kJ/mol.
a) When molten Cs solidifies to Cs (s) at its normal melting point, is the entropy change ΔS positive or negative?
b) Calculate the entropy change S when 15.0 g of Cs(l) solidifies at 28.4 C.

Q4. Using the values for standard molar entropies ΔS_f° from the appendix in your textbook, calculate ΔS° for the following reactions.
a) Be(OH)₂ (s) ? BeO (s) + H2O (g)
b) Mg(OH)2 (s) + 2 HCl (g) ? MgCl2 (s) + 2H2O (l)
c) 2CH4(g) ? C2H6 (g) + H2(g)

Q5. Using the data in the appendix of your textbook, calculate the Gibbs free energy change ΔG° for the following reactions. In each case, indicate whether the reaction is spontaneous or not
a) H2 (g) + Cl2(g) ? 2HCl (g)
b) 2 POCl3 (g) ? 2 PCl3 (g) + O2 (g)

Q6. Consider the reaction 2 NO2 (g)---N2O4 (g)
a) Using the data in the appendix in your text, calculate the standard Gibbs free energy change (ΔG°) for the reaction at 298K.
b) For the above reaction, calculate the value of Keq at 298K
c) For the same reaction, calculate G at 298 K when the partial pressures for NO₂ and N2O4 are 0.40 atm and 0.36 atm, respectively.

Q7. Consider the reaction I2 (g) + Cl2 (g)----2 ICl (g) Kp = 81.9 at 298 K
a) Calculate the standard free energy change (ΔG°)
b) What will be the Free energy change when the above reaction is at equilibrium
c) Calculate G for the reaction at 298 K when PICl = 2.55 atm, PI2=0.325 atm and PCl2 = 0.221 atm

Q8. Consider the decomposition of Lead carbonate PbCO3 (s) ? PbO(s) + CO2 (g)
a) Calculate the Gibbs free energy change (ΔG°) for the reaction at298 K.
b) Calculate G for the reaction at 400 K.
c) Write down the equilibrium expression and calculate the value of Keq at 298 K
d) Calculate the partial pressure of CO2 at 298 K. (Hint: Look at the equilibrium expression and the value of Keq at 298 K)

Q9. For the reaction: 2Al(s) + 3/2 O2(g) ? Al2O3(s), ΔH^o_rxn = -1617 kJ/mol and ΔH^o_rxn = -1577 kJ/mol. Use this data to calculate ΔS^o_rxn reaction at 298 K.

Q10. Calculate the ΔG^o for the following reaction using the data from your text:
2SO2(g) + O2(g) ? 2SO3(g)

Q11. Using the thermodynamic data available from the Appendix(?Go’s), calculate ΔG^o rxn and calculate the equilibrium constant(K) for the reaction at 25 oC:
CaCO3(s) ? CaO(s) + CO2(g)

Q12. What is the minimum temperature required for the spontaneous conversion of CCl4(l) to CCl4(g) when ΔH°(vap) is 57.3 kJ/mol andΔS°(vap) is 164 J/(mol K)? reaction: CCl4(l) ? CCl4(g)

Q13. Given the following
Fe2O3(s) + 3CO(g) . ? 2Fe(s) + 3CO2(g) ΔG° =  29.4 kJ
3Fe2O3(s) + CO(g) . ? 2Fe3O4(s) + CO2(g) ΔG° =  61.6 kJ
Calculate ΔG° for Fe(s) + Fe2O3(s) + CO2(g) ? Fe3O4(s) +CO(g)

Q14. Calculate ΔG° rxn for 2CO(g) + O2(g) ? 2CO2(g) and then calculate ΔG for the reaction at 298K; if the pressure of CO =20. atm,P O2 = 10. atm and P CO2= 0.50 atm. Will increasing the pressure of the reactants make the reaction more or less spontaneous? Explain using your calculations and Le Chatelier’s principle.

Q15. Write the reaction for photosynthesis (production ofC6H12O6(s) and oxygen from carbon dioxide and water as a gas).Calculate ?H, ? S, and ?G for the reaction at standard state. Is the reaction spontaneous?