11)

What are the coefficients in front of NO₃^-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution:
___ NO₃^-(aq) + ___ Cu(s) → ___ NO(g) + ___ Cu²⁺(aq)?

Select one:

A. 3, 6

B. 2, 6

C. 2, 3

D. 3, 4

12)

The values of ΔH°_f for the three states of benzene are approximately -22 kcal/mol, -11 kcal/mol, and 20kcal/mol. Which is the value for solid benzene?

Select one:

A. -22 kcal/mol

B. 20 kcal/mol

C. -11 kcal/mol

D. cannot be determined without additional information

13)

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl₄(l) from 35.0°C to gaseous CCl₄ 76.8°C (the normal boiling point for CCl₄)? The specific heat of CCl₄(l) is 0.857J/gC its heat of fusion is 3.27kj/mol and its heat of vaporization is 29.82kJ/mol.

Select one:

A. 1.43 kJ

B. 6.28 kJ

C. 5.74 kJ

D. 0.896 kJ

18)

When heated, mercury(II) oxide decomposes into elemental mercury and oxygen:
2 HgO(s) → 2 Hg(l) + O₂(g) ΔH° = 181.6 kJ ΔS° = 216.4 J/K
Estimate the temperature at which HgO should begin to decompose if the partial pressure of O₂(g) is constant at 1.00 atm.

Select one:

A. 840°C

B. -34.8°C

C. 34.8°C

D. 566°C

19)

When 50.0 mL of 0.400 M Ca(NO₃)₂ is added to 50.0 mL of 0.800 M NaF, CaF₂ precipitates, as shown in the net ionic equation below. The initial temperature of both solutions is 25.00°C. Assuming that the reaction goes to completion, and that the resulting solution has a mass of 100.00 g and a specific heat of calculate the final temperature of the solution.
Ca²⁺(aq) + 2 F^-(aq) → CaF₂(s) ΔH° = -11.5 kJ

Select one:

A. 24.45°C

B. 26.10°C

C. 26.65°C

D. 25.55°C

Physical chemistry

. The osmotic of an aqueous solution at 351 K is 94 kPa and a density of 1,152 g/mL. Calculate the freezing point (in C) of the solution. The Kf for water is 1.86oC/m.

How does pentobarbital, pancuronium bromide, and potassium chloride accomplish cessation of life?

Please include a source(s)!! It is a necessity! Thank you.

If a temperature scale were bassed on the freezing point (5.5 degrees Celsius) and boiling point (80.1 degrees Celsius) of benzene, and the temperature difference between these two points was divided into 50 units called degrees X, what would be the freezing and boiling points of water in degrees X?

In addition to the molecular orbital treatment of H2, the ground state can be treated by the so-called valence bond (Heitler-London) approach, where individual covalent bonds are combined to form an antisymmetric wave function with spins up and down. Look up this approach and compare the results with the simple MO treatment in terms of bond energy (kJ/mol) and bond distance (pm).

10Na + 2NaNo3 yields 6Na2O + N2

how many grams of sodium oxide will be made by combining 25.0 grams of sodium with 47.0 grams of sodium nitrate?

Balance the given redox reaction.

NaClO₃ + H₂O + I₂ --> HIO₃ + NaCl

?please show all steps

Devise a procedure for the separation and purification of the mixture containing 0.25g benzoic acid, 0.20g benzil, 0.05 p-dichlorobenzene.

Available reagents: 1M NaOH, 1M HCI, 1M NaHCO3, 6 M NaOH, 6 M HCI, saturated solution of NaCl, diethyl ether, 95% ethanol, methanol, isopropyl alcohol, acetone, hexane, toluene, ethyl acetate, anhydrous sodium sulfate.

The Ka of acetic acid is 1.8 x 10^-5 at 25C.

a) What is the pH of a 0.5 M solution of acetic acid at 25C?

b)What is the pH of a solution made up of 20 mL of 0.5 M solution of acetic acid and 10 mL of 0.5 M sodium acetate?

c) If 10 mL of 0.1 M NaOH is added to the solution in part b, what is the final pH?

d) What is the pH of a solution containing equal concentrations of acetic acid and sodium acetate?

1. Would a 50:50 solution of R and S enantiomers of the same compound have any effect on plane polarized light shining through it? Why or why not?

2. Based on your answer to the last question, how could you determine the enantiopurity of a given concentration of a sample if you know its specific rotation [α] using a polarimeter?

3. Give an example of a drug which can be sold as a racemic (R and S) mixture without any harmful effects.

Phosphoric acid is a triprotic acid (K_a1=6.9x10^-8, K_a2 = 6.2x10^-8, and K_a3=4.8x10^-13). To find the pH of a buffer composed of H₂PO₄^- (aq) and HPO₄^2-(aq), which pk_a value would you use in the Henderson-Hasselbalch equation? Calculate the pH of a buffer solution obtained by dissolving 22.0 g of KH2PO4 and 32.0 g of Na2HPO4 in water and then diluting to 1.00 L

Calculate the hydronium ion concentration and the pH at the equivalence point when 65.0 mL of 0.4000 M NH3 is mixed with 35.0 mL of 0.7429 M HCl.

Ka=5.6x10-10

Balance the following using the ½ reaction method Permanganate ion plus bromide ion yields (MnO4) and BrO3 - (basic solution)

Describe the process for determining the orbital diagram for an atom, including the number of orbitals and electrons for each subshell. Describe how quantum numbers relate to the orbital diagrams. How does this quantum mechanical view of the atom differ from the Bohr model of the atom?

Part A Suppose that the microwave radiation has a wavelength of 11.6 cm . How many photons are required to heat 275 mL of coffee from 25.0 ∘C to 62.0 ∘C? Assume that the coffee has the same density, 0.997 g/mL , and specific heat capacity, 4.184 J/(g⋅K) , as water over this temperature range.

Express the number of photons numerically.