1. Equilibrium
2SO3(g) <--> O2(g) + 2SO2(g)
A 3.21g sample of sulfur trioxide is placed in a 2.25 L cylinder and allowed to reach equilibrium at a constant temperature of 500 , as shown in the above equation. Analysis shows 1.23 X 10^-2 mol of sulfur dioxide at equilibrium.
a. Write the equilibrium constant expression (Kc) for this system.
b. Calculate the concentration of all three gases at equilibrium.
c. Calculate the Kc value for this system.
d. Calculate the value of Kp at this same temperature.
I know the answer to a. is Kc = [O2][SO2]^2/[So3]^2
I don't know about b,c, or d.
2.
a. Ammonia gas is added to boron trichloride gas.
Identify the Lewis acid in this reaction.
b. Potassium oxide solid is added to water. What is the expected pH of the solution.
c. Concentrated ammonia solution is added to copper (II) nitrate solution. How might the product be identified?
3. Explain the following observations:
a. WHen a solid is heated at its melting temperature, the temperature does not increase.
b. The melting temperature of KCl is less than that of NaF.
c. Liquid bromine and ICl have almost the same molecular mass, but ICl boils at a temperature 40 degrees Celsius higher than Br2.
d. The boiling temperature of HCl is lower that that of HF.
e. When alcohol (ethanol) is poured over your arm, your skin feels cold.
It is best to post a single question. Here you have three questions with multiple parts for a total of about 13 questions. We will get to them one by one.
1. Equilibrium
2SO3(g) <--> O2(g) + 2SO2(g)
A 3.21g sample of sulfur trioxide is placed in a 2.25 L cylinder and allowed to reach equilibrium at a constant temperature of 500 , as shown in the above equation. Analysis shows 1.23 X 10^-2 mol of sulfur dioxide at equilibrium.
a. Write the equilibrium constant expression (Kc) for this system.
b. Calculate the concentration of all three gases at equilibrium.
(SO2) = mols SO2/Liters.
(O2) = 1/2 (SO2)
(SO3) = [(mols SO3 initially)-mols SO2 at equilibrium)]/Liters.
c. Calculate the Kc value for this system.
Plug values from part b into your answer for part a and calculate Kc.
d. Calculate the value of Kp at this same temperature.
Look up the equation for converting Kc to Kp and calculate
Your answer to a is correct
2.
a. Ammonia gas is added to boron trichloride gas.
Identify the Lewis acid in this reaction.
Draw the Lewis electron dot structure for NH3 and for BF3. Look to see which molecule gives the electrons and which molecule receives the electrons. Remember that a Lewis acid is an electron acceptor.
b. Potassium oxide solid is added to water. What is the expected pH of the solution.
What is the equation? Oxides of group IA and IIA metals react with water to form bases.
c. Concentrated ammonia solution is added to copper (II) nitrate solution. How might the product be identified?
It all depends upon how much NH3 is added. Just a small amount will produce a precipitate of Cu)OH)2. More NH3 will produce Cu(NH3)4^+2 which is a complex ion that has a deep blue/purple color.
3. Explain the following observations:
a. WHen a solid is heated at its melting temperature, the temperature does not increase.
b. The melting temperature of KCl is less than that of NaF.
c. Liquid bromine and ICl have almost the same molecular mass, but ICl boils at a temperature 40 degrees Celsius higher than Br2.
d. The boiling temperature of HCl is lower that that of HF.
e. When alcohol (ethanol) is poured over your arm, your skin feels cold.
These are thought questions. Post your thoughts and someone will critique them.
4 answers