Consider the titration of a 23.0 −mL sample of 0.100 M HC2H3O2HC2H3O2 with 0.125 MMNaOH. Determine each of the following.

a.) the initial pH

b.) the volume of added base required to reach the equivalence point

c.) the pH at 5.00 mLmL of added base

d.) the pH at one-half of the equivalence point

e.) the pH at the equivalence point

f.)

Determine the [OH−] , pH, and pOH of a solution with a [H+] of 0.0018 M at 25 °C.

[OH−]=

pH=

pOH=

Determine the [H+] , pH, and pOH of a solution with an [OH−] of 7.3×10−7 M  at 25 °C.

[H+]=

pH=

pOH=

Determine the [H+] , [OH−] , and pOH of a solution with a pH of 3.67 at 25 °C.

[H+]=

[OH−]=

pOH=

Determine the [H+] , [OH−] , and pH of a solution with a pOH of 5.18 at 25 °C.

[H+]=

[OH−]=

pH=

The fusion of deuterium and tritium produces 2.8×10−12J for every atom of deuterium and atom of tritium. Part A How much energy is produced per mole of deuterium and mole of tritium. Express your answer using two significant figures.

9a) A sample of an unknown gas is found to have a density of 1.07 g/L at a pressure of 0.783 atm and a temperature of 56 °C. Assume ideal behavior. The molar mass of the unknown gas is ____g/mol.

b) A sample of oxygen gas has a density of _____g/L at a pressure of 1.20 atm and a temperature of 38 °C. Assume ideal behavior.

c) A mixture of xenon and oxygen gases, in a 6.72 L flask at 39 °C, contains 38.4 grams of xenon and 3.82 grams of oxygen. The partial pressure of oxygen in the flask is ____atm and the total pressure in the flask is ____atm.

d) A mixture of carbon dioxide and hydrogen gases is maintained in a 5.96 L flask at a pressure of 2.47 atm and a temperature of 32 °C. If the gas mixture contains 16.1 grams of carbon dioxide, the number of grams of hydrogen in the mixture is _____g.

HCl and H2SO4

• Identify the poster’s two additional molecules (HCl and H2SO4) as ionic or covalent and then name them according to IUPAC rules.
• Discuss how you identified each as ionic or covalent and how you named each.
• Provide the common name for each molecule, if possible.
• Explain what each molecule is and how it can be used or where it is found.

When 25.0 mL of a 6.23×10-4 M sodium carbonate solution is combined with 15.0 mL of a 7.76×10-4 M lead acetate solution does a precipitate form? yes (yes or no)

For these conditions the Reaction Quotient, Q, is equal to ____?

After reacting 1.45 g of salicylic acid with 5.0 mL of acetic anhydride, 1.75 g of acetylsalicylic acid is obtained. What is the calculated percent yield? Provide your answer to the correct number of significant figures.

Explain briefly why each of the following is not a possible set of quantum numbers for an electron in an atom. In each case, change the incorrect value to make the set valid.

What is the correct value for each set?

a) n = 4, ℓ = 2, mℓ = 3, ms = + ½

b) n = 3, ℓ = 3, mℓ = 0, ms = – ½

c) n = 3, ℓ = 2, mℓ = – 1, ms = 0

In a 0.15M aqueous solution of butanoic acid C3H7CO2H , what is the percentage of butanoic acid that is dissociated? You can find some data that is useful for solving this problem in the ALEKS Data resource.

Round your answer to 2 significant digits.

Help PLs

The equilibrium constant in terms of pressures for the reduction of tungsten(IV) oxide to tungsten at 25 °C is K_p = 3.82×10^-4, corresponding to the reaction

• WO₂(s) + 2CO(g) = (double arrow) W(s) + 2CO₂(g)

If the total pressure of an equilibrium system at 25 °C is 2.67 atm, calculate the partial pressures of CO(g) and CO₂(g).

P_CO =  atm

P_CO2 =  atm

If 0.580mol  of a nonvolatile nonelectrolyte are dissolved in 3.50mol of water, what is the vapor pressure PH2O of the resulting solution? The vapor pressure of pure water is23.8 torr at 25 ?C .

In solutions composed of two liquids (A and B), each liquid contributes to the total vapor pressure above the solution. The total vapor pressure is the sum of the partial pressures of the components:

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A 2.500×10^-²M solution of NaCl in water is at 20.0?C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.3mL . The density of water at 20.0?C is 0.9982 g/mL.

a)Calculate the molality of the salt solution.

b)Calculate the mole fraction of salt in this solution.

c)Calculate the concentration of the salt solution in percent by mass.

d)Calculate the concentration of the salt solution in parts per million.

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Atmospheric pressure is 1.01 bar, but air is only composed of 21.0% (by moles) oxygen. Thus, the partial pressure of oxygen in air is less than 1.01 bar. What is the millimolar concentration of dissolved oxygen for a lake or stream under the partial pressure of oxygen and a temperature of 16?C?

For the next three problems, consider 1.0 L of a solution which is 0.6 M HC₂H₃O₂ and 0.2 M NaC₂H₃O₂ (K_a for HC₂H₃O₂ = 1.8 x 10^-5). Assume 2 significant figures in all of the given concentrations so that you should calculate all of the following pH values to two decimal places.

1. Calculate the pH of this solution.

2. Calculate the pH after 0.10 mol of HCl has been added to the original solution. Assume no volume change on addition of HCl.

3. Calculate the pH after 0.20 mol of NaOH has been added to the original buffer solution. Assume no volume change on addition of NaOH.

For Bromocresol Green, which of the following reactions (if any) would it be appropriate to use your indicator to determine the endpoint for the reaction?  Circle YES or NO for each reaction.  3 pts

• Hydrochloric acid and citric acid    YES or NO
• Hydrochloric acid and sodium hydroxide     YES or NO
• Acetic acid and ammonia    YES or NO

1. The tetraborate ion present in a 5.00 mL sample of a saturated borax solution is titrated with 4.78 mL of 0.209 M HCl. Express all calculations with the correct units and number of significant figures.

a. How many moles of B₄O₅(OH)₄^2- are present in the sample?

b. What is the molar concentration of B₄O₅(OH)₄^2- in the sample?

c. What is the K_sp of the dissolution of borax at this temperature?

Arrange the following molecules in order of increasing average molecular speed.

NO2 at 327K, He at 443K, He at 386K, O2 at 386K

Enter formulas and temperatures in the boxes below: 1 = slowest, 4 = fastest