Describe the nature of colloidal precipitate particles. (describe the electric double layer) ,Why do they tend to not settle, and What factors control coagulation of a colloidal particles?

Gas Laws

Units in Gas Law Problems

One problem associated with gas law problems is unit agreement. It is important that pressure, volume and temperature units match or agree within a problem. Solve 1-4 using the factor-label method. Problems 5 and 6 are done without factor-label.

1. Convert 1.52 atm to kPa 2. Convert 85 kPa to mmHg

3. Convert 156.3 mmHg to atm 4. Convert 950 torr to kPa

5. Convert -250.0 °C to K 6. Convert 253 K to °C

Boyle’s Law

7. Equation for Boyle’s Law:

8. A gas occupies 12.3 L at 825.7 mmHg. What will the pressure be when the volume is 75 L?

9. A gas occupies 25 L at 2.5 atm. What is the volume if the pressure changes to 1.5 atm?

10. You have 50 L of CO₂ gas at standard temperature and pressure (STP). What would need to be done to the pressure to cut the volume of gas in half?

Charles’ Law

11. Equation for Charles’ Law:

12. How do these two factors relate to each other?

13. What does temperature actually measure?

14. At 27.8 °C, a gas occupies 1500 m. What volume will it have at 100.0 °C?

15. What temperature (in K) must a gas be if it occupied 1.396 L at 72.3 °C and now occupies 1.044 L?

Gay-Lussac’s Law

16. Equation for Charles’ Law:

17. A gas cylinder contains nitrogen gas at 10-atm pressure and a temperature of 20˚C. The cylinder is left in the sun, and the temperature of the gas increases to 50˚C. What is the pressure in the cylinder?

18. A bike tire has a volume of 0.850L at a pressure of 40 psi and 0˚C. What will be the pressure of the tire at 35˚C?

19. An aerosol can has a fixed volume of gas at 4.0-atm of pressure and room temperature (25˚C). If the pressure inside the can reaches 5.9-atm the can will explode. The can is thrown into a fire that is 400˚C. Will the can explode? Show all calculations to support your answer.

You would like to make 100.00 mL of a 4.76 pH acetic acid/acetate buffer, in which the acid concentration is 0.070M. Write the reaction of the buffer with HCl solution. How many mL of 0.100 M HCl can react with the buffer before it is exhausted? And Write the reaction of the buffer with NaOH solution. How many mL of 0.100 M NaOH can react with the buffer before it is exhausted?

#16.110 A 130.0 −mL sample of a solution that is 2.9×10−3 M in AgNO3 is mixed with a 225.0 −mL sample of a solution that is 0.10 M in NaCN.

After the solution reaches equilibrium, what concentration of Ag+(aq) remains?

Predict the colors that the following aqueous solutions will produce in a flame test:

1. CaF₂(aq)

2. NaOH(aq)

3. CuCO_3(aq)

An explanation for why each aqueous solution is their respective color would aid me in understanding the concept. Thank you so much!

85. Antimony pentachloride decomposes according to this equation:
SbCl5(g) ⇌ SbCl3(g) + Cl2(g)
An equilibrium mixture in a 5.00-L flask at 448 °C contains 3.85 g of SbCl5, 9.14 g of SbCl3, and 2.84 g of Cl2. How many grams of each will be found if the mixture is transferred into a 2.00-L flask at the same temperature?

89. A 1.00-L vessel at 400 °C contains the following equilibrium concentrations: N2, 1.00 M; H2, 0.50 M; and NH3, 0.25 M. How many moles of hydrogen must be removed from the vessel to increase the concentration of nitrogen to 1.1 M? The equilibrium reaction is
N2(g) + 3H2(g) ⇌ 2NH3(g)

Describe the three sources of loss in the lab preparation of methyl benzoate from benzoic acid.

One source is mechanical.

A sample of cells with a total receptor concentration of 50 mM was incubated with a ligand concentration of 100 mM. Following the incubation period, the concentration of unbound receptors was determined to be 15 mM. What is the Kd for the receptor-ligand interaction?

A) 28 mM

B) 43 mM

C) 143 mM

D) 217 mM

E) 333 mM

1. If a single electron in an excited hydrogen atom is occupying the 3^rd energy level and then relaxes back to the ground state, how much energy is released in the form of electromagnetic radiation?

1.The Cu2+ ions in this experiment are produced by the reaction of 1.0g of copper turnings with excess nitric acid. How many moles of Cu2+ are produced?

2. Why isn't hydrochloric acid used in a direct reaction with copper to prepare the CuCl2 solution?

3. How many grams of metallic copper are required to react with the number of moles of Cu2+ calculated in Problem 1 to form the CuCl? The overall reaction can be taken to be: Cu2+(aq) + 2Cl-(aq) + Cu(s) -----> 2CuCl(s)

4. What is the maximum mass of CuCl that can be prepared from the reaction sequence of this experiment, using 1.0g of Cu turnings to prepare the Cu2+ solution?

5. A sample of the compound prepared in this experiment , weighing 0.1021g, is dissolved in HNO3, and diluted to a volume of 100 ml. A 10ml aliquot of that solution is mixed with 10 mL 6M NH3. The [Cu(Nh3)4]2+ in the resulting solution is found to be 5.16 x 10^-3 M.

a. How many moles of Cu were in the original sample, which had been effectively diluted to a volume of 200 mL.

b. How many grams of Cu were in the sample?

c. How many grams of Cl were in the sample? How many moles?

d. What is the formula of the copper chloride compound?

describe how you would prepare 1.25L of a 0.025 M sucrose solution from a stock solution with concentration of 5.00 M.

1.Pyridine is a weak base that is used in the manufacture of pesticides and plastic resins. It is also a component of cigarette smoke. Pyridine ionizes in water as follows: C5H5N+H2O⇌C5H5NH++OH− C 5 H 5 N + H 2 O ⇌ C 5 H 5 N H + + O H − The pKb p K b of pyridine is 8.75. What is the pH p H of a 0.320 M M solution of pyridine? Express the pH p H numerically to two decimal places.

2.

Benzoic acid is a weak acid that has antimicrobial properties. Its sodium salt, sodium benzoate, is a preservative found in foods, medications, and personal hygiene products. Benzoic acid dissociates in water:

C6H5COOH⇌C6H5COO−+H+C6H5COOH⇌C6H5COO−+H+

The pKapKa of this reaction is 4.2. In a 0.51 MM solution of benzoic acid, what percentage of the molecules are ionized?

Is the reduction of benzoin to hydrobenzoin using NaBH4 and EtOH stereoselective: will only meso (cis) product be formed or a mixture of meso/racemic products?