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200
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400
Thermochem
Solutions and such
Acids and Bases
Equilibrium
100
200
100
500
400
300
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100
500
400
300
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500
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300
Thermochem 100
The total energy of the world is constant. Energy can neither be created
nor destroyed.
What is the law of conservation of energy?
Thermochem 200
What is the equation for a change in temperature?
ΔT = Tf - Ti
Thermochem 300
In the equation for calculation of heat transfer: q= mcΔT what does each letter
represent?Q = heat m= mass c = specific heat capacity ΔT = change in
temperature
Thermochem 400
What is the equivalence of 0ºC in Kelvins?
273.15K
Thermochem 500
How do you spell …
LOLCalculate the specific heat capacity of canola
oil. If the mass of the oil is 60g, the initial temperature is 35ºC and the final temperature
is 5.2ºC with a heat change of 4.0x103?
C= q/m∆T = -4.0x103J
(60.0g)(5.2ºC – 35.0ºC) = 2.24 J/gºC (pg 635)
Solutions and Such 100
Is ethanol (CH3CH20H) soluble in water?
Yes, infinitely soluble!
Solutions and Such 200
True or False, Polar compounds can dissolve in non-polar solvents. Explain.
False, polar compounds can only dissolve polar solvents and non-polar compounds can only dissolve in non-polar solvents!!
Solutions and Such 300
Define Miscibility and give an example of a misicble and immisicble solution.
Miscible – compounds that dissolve readily in each other in any proportion. (example: water
and alcohol)
Immiscible – liquids that do not readily dissolve in each other (example oil and water)
Solutions and Such 400
What is a dipole – dipole attraction?
The attraction between the opposite charge on two different
polar molecules is called a dipole – dipole attraction.
Solutions and Such 500
Calculate the volume of isoproply alcohol used to make a 500mL solution.
The volume/volume % is 70%.
Volume/volume percent = volume of solute x 100% volume of solution
Volume of solute = 70% x 500mL100%
= 350mL (pg 262)
Equilibrium 100
What is Le Châtelier’s Principle?
If a stress is applied to a system at equilibrium, the equilibrium will shift to
relieve the stress.
Equilibrium 200
Given the balanced formula:
2SO2(g) + O2 2SO3(g) + heat Increase SO2 concentration
Increase temperatureWhich way will the reaction shift?
Increase SO2 concentration = shift right
Increase temperature = shift left
Equilibrium 300
What is a catalyst, and how does it affect a reaction?
A catalyst is a substance that increases the rate of a chemical reaction without being consumed by the reaction. The catalyst is always left over.
Equilibrium 400
For the Reaction: CO(g)+NO2(g) CO2(g)+NO(g)
Given the ΔE= -226kJ and the Ea(fwd)= 134kJ
What is the Ea(rev)?
ΔE=Ea(rev)-Ea(fwd)
Ea(rev)=ΔE+Ea(fwd)
Ea(rev)=360Kj
Equilibrium 500
Step one: NO2(g) + NO2(g) NO3(g)+NO(g)
Step two: NO3(g)+CO(g) NO2(g)+CO2(g)
NO2(g)+NO2(g)+NO3(g)+CO(g) NO3(g)+NO(g)
+NO2(g)+CO2(g)
The Balanced Equation is: NO2(g)+CO(g) NO(g)+CO2(g)
The reaction Intermediate is NO3.
Given the following two step reaction:
Step one: NO2(g) + NO2(g) NO3(g)+NO(g)
Step two: NO3(g)+CO(g) NO2(g)+CO2(g)
What is the overall balanced equation for the reaction and what is the reaction intermediate.
Acids and Bases 100
What are the properties of an acid?
•pH between -1 and 7
•Sour taste
•Strong acids dissociate completely
•Conduct electricity
•Turns blue litmus paper red
•Have no characteristic feel
•Neutralize basic solutions, forming salt and water
Acids and Bases 200
Explain the Arrhenius, and the Brǿnsted Lowry Theories.
Arrhenius theory states: An acid is a substance that dissociates in water to produce one or more hydrogen ions, H+. A Base is a substance that dissociates in water to produce one or more Hydroxide ions, OH ֿ.
Brǿnsted Lowry theory states: An acid is a substance from which one proton (H+ ion) can be removed. A base is a substance that can
remove a proton (H+ ion) from an acid.
Acids and Bases 300
Identify the conjugate acid-base pairs of the following reaction:
HBr(g)+H2O(l) H3O+(aq)+Brˉ
HBr(g)+H2O(l) H3O+(aq)
+Brˉ
Conjugate acid-base pair
Conjugate acid-base pair
Acids and Bases 400
Calculate the pH of a solution with [H3O+]=3.8x10-3.
pH= -log(H3O+)
pH= -log(3.8x10-3)
pH= 2.42
Acids and Bases 500Given:
CH3CH2COOH(aq)+H2O(l) CH3CH2COOֿ(aq)+H3O(aq)
The initial [CH3CH2COOH]= 0.10 mol/L and pH= 2.96
Find Ka.
Concentration (mol/L) CH3CH2COOH(aq)+ H2O(l) CH3CH2COOֿ(aq)+ H3O(aq)
Initial 0.10 0 0
Change -x +x +x
Equilibrium 0.10 – x +x +x
Ka= (x)(x) (0.10-x)
[H3O+]= 10-2.96
[H3O+]= 1.1 x 10-
3
Ka= (1.1x10-3)(1.1x10-3) (0.10-1.1x10-3)
Ka= 1.2x10-5