: Let’s consider second-law thermodynamics again, we define S_univ=S_sys + S_surr

1. Explain the physical meaning of three symbols here: S_univ, S_sys , S_surr

2. Which of these three determines if a proposed process is spontaneous or not? State what sign it needs to be for the proposed process to be spontaneous?

What difference in the properties of 0.1 M HCl and 0.1 M acetic acid caused the pH's of equal volumes of each to differ?

What is the percent water by weight of lithium perchlorate trihydrate?

1. An enzyme has a molecular weight of 25,000. If V_max= 80umol/min and you use 500uL of a 1mg/mL solution of enzyme, what is the turnover number?

2. In an enzyme activity assay, a 100uL assay sample containing 3.2 x 10^-5 M enzyme produced an absorbance change per minute of 0.42. The molecular weight of the enzyme is 17,000 g/mol and the extinction coefficient is 6220 M^-1 cm^-1.

What is the activity of the enzyme?

What is the specific activity of the enzyme?

1. Glucose has a solubility of 125 g /100 mL. What is the approximate concentration of glucose in a
saturated solution? How much glucose can be dissolved in 745 mL of water?
[glucose] _________ M
Glucose _________ g
2. Determine whether the following salts or molecules will have higher or lower solubility in water
at higher temperatures.
KCl(s) + H2O(l) KCl(aq), ?Hrxn > 0 __________
NH3(g) + H2O(l) NH3(aq), ?Hrxn< 0 __________
3. BaF2 has a Ksp of 2.45 x 10-5. What is the solubility of BaF2? What is the F-
concentration in a
saturated barium fluoride solution?
Solubility of barium fluoride ___________
[F-]= _______

Discuss how screening can be used for mass spectra

#3 R&D Exp. 26

Should Cu(OH)₂ precipitate in 3 M NH₃ if the original [Cu²⁺] is 0.1 M ( the K_b for ammonia is 1.6x10^-5)?

Please show work and explain a little of how you got this result

Calculate the pH of each of the following strong acid solutions.
(a) 0.00512 M HBr

pH =  

(b) 0.633 g of HI in 18.0 L of solution

pH =  

(c) 44.0 mL of 3.90 M HBr diluted to 1.30 L

pH =  

(d) a mixture formed by adding 89.0 mL of 0.00215 M HBr to 89.0 mL of 0.000310 M HI

pH =  

Assuming 100% dissociation, calculate the freezing point and boiling point of 2.79 m K3PO4(aq). Constants may be found here.

Identify the incorrect statement

A) At equilibrium the concentration of the rectants is equal to the concentration of the products

B) A change in temp will change the value of the equilibrium constant

C) Removing reactants from a system at equilibrium shifts the reaction left

D) Decreasing the pressure of a system at equilibrium shifts the reaction tward the side with the most gas molecules

E) All of the above are correct

Please explain how you got your answer

Can anyone explain the complete mechanism of a nitrile with a grignard reagent to form a ketone?

1. Write the solubility equilibrium and the solubility product expression for the following sparingly soluble salts.

CaCO3

Cu2S

Sb2S3

2. The solubility of silver bromide, AgBr, at 25

Here are some problems and their answers. I would appreciate if someone could please explain step by step how to get these answers? I need to understand this concept.

The following questions refer to the equilibria: 2 NaHCO3(s) ⇌ Na2CO3(s) + H2O(g) + CO2(g) K(110°C)=0.68

1)If CO2(g) is added to the equilibrium mixture the partial pressure of H2O(g) will: answer: Decrease (how and why??)

2) If the volume of the container is decreased, the amount in grams of sodium carbonate (Na2CO3(s)) will: Answer: decrease (I thought volume only affects gases??)

3)The ΔH of the reaction was measured and determined to be -25 kJ/mole of sodium bicarbonate (NaHCO3). If the reaction were run at 150°C, a possible value for K could be: answer: 0.54

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This next question is not involved with the above.

4) What is the pH of the solution after 30 mL of 0.12 M HCl is mixed with 60 mL of 0.12M NaOH? Answer: . 12.60

which species will have the greatest absolute entropy at 25 degrees celcius Ne (g),
C2H2(g)
Ne (g)

H2O(l)
C2H5OH (l)
C4H10 (g)

thanks