1. Final Jeopardy Subterm 2 Solutions* Equilibrium* Acids & Bases*
Thermochemistry*
Redox
Nuclear Chemistry*
Organic Chemistry

2. Calculate the H for this reaction: C2H4(g) + H2(g)  C2H6(g)
THERMO
Calculate the H for this reaction: C2H4(g) + H2(g)  C2H6(g)
(H f for C2H4(g) = 52.5 kJ/mol;
Hf for C2H6(g) = kJ/mol)

3. Solutions
What is the maximum amount of KCl that can dissolve in 500 g of water?
(solubility of KCl is 34 g / 100 g H2O at 20C)
34 x 5 = 170 g

4. What three operations makes a substance dissolve faster in a solvent?
Solutions
What three operations makes a substance dissolve faster in a solvent?
Heating
Agitation/stirring
Smaller surface area/particle size

5. Solutions
If the solubility of a particular solute is 10g/100g H2O at 20C, what solution concentrations would represent a supersaturated aqueous solution of that solute?
5g/100g H20
20g/200g H20
25g/300g H20
55g/500g H20

6. Solutions
What is the molarity of a solution that contains 6 moles of solute in 2 liters of solution?
6mol/2L = 3M

7. Solutions
What mass of sucrose, C12H22O11, is needed to make mL of a 0.200M solution?
0.200M = x/0.500L
X = 0.1mol x (342g/mol)
= 34.2 g

8. Solutions
To 205 mL of a 0.75M solution of KI, a student adds enough water to make 1.5 L of a more dilute KI solution. What is the morality of the new solution?
M1V1 = M2V2
M2 = 0.10 M

9. Solutions
What is the boiling point of a solution that contains 4.6 moles of KBr in 1500 g of water? (Kb = 0.512C/ m; gram formula mass of water = 18 g)
T = kbmn
T = (0.512)(4.6mol/1.5kg)(2)
103.1 oC

10. Soltions
What is the freezing point of a solution of 0.80 mol of LiBr in 850 mL of water? (Kf = 1.86C/m)
-3.5 oC

11. Equilibrium
What is the expression for Keq for this reaction? 2H2O(g)  2H2(g) + O2(g)

12. Equilibrium
Calculate the equilibrium constant for the production of MgO when the equilibrium concentrations are 0.030M of Mg, 0.020M for O2, and 2.0 M for MgO?

13. Equilibrium
In an endothermic reaction at equilibrium, what is the effect of lowering the temperature?
The system will shift toward to reactants (to the left) and more reactants will be made.

14. Equilibrium
What is the effect of adding more hydrogen gas in the following equilibrium reaction?
C2H2(g) + H2(g)  C2H4(g)
More products will be made
(the system will shift right)

15. How does a decrease in pressure affect the following reaction?
Equilibrium
How does a decrease in pressure affect the following reaction?
C2H2(g) + H2(g)  C2H4(g)
The system will shift towards the left (or the reactants)

16. Thermo What does entropy measure?
The amount of chaos (disorder) in a system

17. Thermo
What physical state of carbon dioxide has the highest entropy (solid, liquid, or gas)?
GAS

18. Acids & Bases
When an acid reacts with a base, what two types of compounds are formed?
Salt and Water

19. Acids & Bases
If the [H+] in a solution is 1 x 10-1 mol/L, what is the [OH-]?
1x10-13mol/L

20. Acids & Bases
If the pH is 4, what is the concentration of hydrogen ion?
1x10-4M

21. Acids & Bases What is an acid according to Arrhenius?
Gives off hydrogen ions in solution

22. Acids & Bases What characterizes a strong acid or base?
Dissociates completely in water

23. Acids & Bases
What is the concentration in normals of sulfuric acid if 34.5 mL of acid is neutralized by 20.0 mL of 1.0 M sodium hydroxide?
0.58 N

24. Acids & Bases What does a buffer do?
A buffer helps keep the pH of a solution stable

25. Thermo
How much heat is absorbed by a 15.5 g piece of gold as it is heated from 4.5°C to 177.4°C? (the specific heat of gold is J/g°C)
q = mct
q = (15.5g)(0.129 J/g°C)(172.9 °C)
q = 346 J

26. Thermo
How mcuh energy is needed to heat164.5 g ice at -27.6oC to 0.00oC?
9,490 J

27. Nuclear
1. The half-life of radon-222 is four days. After how many days is the amount of radon-222 one-eighth of its original amount?
12 days

28. Nuclear
1. What particle is needed to complete this nuclear reaction?

29. Nuclear
What particle is needed to complete this reaction?

30. Nuclear
A piece of wood found in an ancient burial mound contains only one-fourth as much carbon-14 as a piece of wood cut from a living tree growing nearby. If the half-life (t1/2) for carbon-14 is 5730 years, what is the approximate age of the ancient wood?
11,500 years

31. Nuclear
Nitrogen-13 decays to carbon-13 with a half-life of 10.0 minutes. Assume that you are given a starting mass of 2.00 grams of nitrogen-13. How many grams of nitrogen-13 will remain after 42.7 minutes?
0.104 grams

32. Final Jeopardy is next Teams, place your bets
You may bet between 0 pts - max points you have.
Each team will need to write down their final answer and bring it up for the judges to score.
You have as much time as you need (within reason)

33. Final Jeopardy
How much energy is needed to heat a 42.3 g sample of ice at –35.7°C to steam at 112.0°C?
132 kJ