The solubility of O2 (g) in water at 0 oC = 14.74 mg/L. The solubility decreases to 7.03 mg/L at 35 oC.

Calculate kH (Henry’s Law Constant) for water at these temperatures.

partial pressure=0.21

Calculate the standard enthalpy change for the following reaction at 25 degrees C.

HCl(g) + NaOH(s) ---> NaCl(s) + H₂O(l)

Platinum has a specific heat of 0.133 J/gK. If 250.0 g of platinum at 1000.0°C is dropped into 115mL of water
at 20.0 °C, will the water boil?

Citric acid (192.13 g/mol) is a triprotic acid with the following chemical formula: H3C6O7H5.

The acid dissociation constants for citric acid are:

Ka1 = 7.1 x 10^-4 M; Ka2 = 1.7 x 10^-5 M; Ka3 = 6.4 x 10^-6 M

Describe how you would prepare at least 100.00 mL (you may make more) of a citrate buffer with a pH of about 4.40. You have available distilled water, volumetric flasks and any sodium salts you desire. You must indicate the amount in grams of material needed (except for water, you may use volume). Your designed buffer must have a reasonable buffer capacity and no solution you make can have a concentration greater than 0.500 M.

In the replacement reaction of magnesium nitrate with tin, how many grams of magnesium would be produced if 58.9 mg of magnesium nitrate? Report your answer with 3 significant figures.

2 Mg(NO3)2 + Sn → Sn(NO3)4 + 2 Mg

9.) As mentioned below, you are required to design your own procedure for determining the heat of dissolution of your chosen salt with a coffee cup calorimeter. Answer the following questions and consider them in designing this procedure:

a.) When you find your initial temperature Ti, should you take one measurement from the thermometer as soon as you place it in the water in the calorimeter? Why or why not? If not, what should you do instead?

b.) Do you expect the temperature of the water in the calorimeter to rise, fall, or stay the same after you add your salt? If the temperature will change, will it continue to change indefinitely or not?

c.) How will you know your dissolved salt solution has reached it's maximum or minimum temperature, i.e. what will you observe in your data to indicate this has happened?

d.) Should you repeat your experiment? Why or why not? If so, what could you change from trial to trial? (Think about what parameters you have control over and remember that you're trying to optimize your system!). Give two possible suggestions. Should you change both or just one? Which one would be easier to change from trial to trial?

A 30.0- mL sample of 0.165 M propanoic acid is titrated with 0.300 MKOH . Part A Calculate the pH at 0 mL of added base. Part B Calculate the pH at 5 mL of added base. Part C Calculate the pH at 10 mL of added base. Part D Calculate the pH at the equivalence point. Part E Calculate the pH at one-half of the equivalence point. Part F Calculate the pH at 20 mL of added base. Part G Calculate the pH at 25 mL of added base.

What does the valence of the individual atom have to do with ionic and covalent bonding forces?

Vanillin Reduction with Sodium Borohydride to form Vanillyl Alcohol

Started with 2.517g vanillin and 5.0mL NaBH₄

Crude Product= 7.568g

Recrystallized Product= 2.297g

a) Calculate the %yield for both the crude and "fully" synthesized product

b) Explain why this is likely not 100%. How could this be improved

c) Draw mechanism

A 2.550

The elimination experiment performed this week proceeds via E2 mechanism according to the textbook. As you have learned in lecture, there is stereoselctivity as well as regioselctivity associated with the E2 mechanism. What do you expect the products of reaction to be? Which is the major product and which is the minor product? Explain your answer from both setereoselctivity and regioselectivity aspects.

For the following reaction, 15.1 grams of nitrogen monoxide are allowed to react with 5.41 grams of oxygen gas .

nitrogen monoxide(g) + oxygen(g) nitrogen dioxide(g)

What is the maximum mass of nitrogen dioxide that can be formed? ( grams )

What is the FORMULA for the limiting reagent?  

What mass of the excess reagent remains after the reaction is complete? (grams)

1- a. If ΔHsolution is slightly endothermic, a solution might form. Explain why
b. If ΔHsolution is highly endothermic, a solution can never form. Explain why.
c. If ΔHsolution is exothermic, a solution will always form. Explain why.

Explain how an organic solvent like hexane could inhibit enzyme action. . Explain how addition of base could inhibit enzyme action.

Consider the following reaction:

2A+3B→3C+2D

Use the following data to determine the rate of reaction in terms of the disappearance of reactant A at time = 20 s.

Part B::Consider the following reaction:

2A+3B→3C+2D

Use the following data to determine the rate of reaction in terms of the appearance of product C when the time is 20 s.

Part C:
Consider the following reaction:

A+B→C+D

The initial concentrations of the reactants A and B are 0.280 M and 0.200 M, respectively.

The rate of reaction is 0.060 M⋅s−1, and the orders of the reaction, with respect to reactants A and B, are 1 and 2, respectively.

Determine the rate constant (k) for the reaction using the rate law.