Final JeopardySubterm 2

Gases*

Solutions*

Equilibrium*

Acids & Bases*

Thermochemistry*

Nuclear Chemistry*

Gases 100

According to Boyle’s Law, as volume increases what does pressure do? (increase, decrease or no change)

Pressure decreases

Gases 200

According to Charles’ Law, how are temperature and volume related– inversely or directly?

Directly related

Gases 300

The combined gas laws incorporates what three properties of a gas?

Temperature, Volume and Pressure

Gases 400 What volume would 50.0 g of

ethane, C2H6, occupy at 140 ºC under a pressure of 1820 torr?(R = 0.0821 L-atm/moles-K)

V = (1.66 mol) (0.0821 L·atm/mol·K)(413 K)

(2.39 atm)

V = 23.6 L

Gases 500

Under the same conditions of temperature and pressure, how many times faster will hydrogen effuse compared to carbon dioxide?

2 44.01 /4.67

2 2.02 /

rateH g mol

rateCO g mol

Solutions 100

What three operations makes a substance dissolve faster in a solvent?

Heating

Agitation/stirring

Smaller surface area/particle size

Solutions 200

If the solubility of a particular solute is 10g/100g H2O at 20C, what solution concentrations would represent a supersaturated aqueous solution of that solute?

a) 5g/100g H20

b) 20g/200g H20

c) 25g/300g H20

d) 55g/500g H20

Solutions 300What is the molarity of a solution that contains 6 moles of

solute in 2 liters of solution?

6mol/2L = 3M

Solutions 400

What mass of sucrose, C12H22O11, is needed to make 500.0 mL of a 0.200M solution?

0.200M = x/0.500L

X = 0.1mol x (342g/mol)

= 34.2 g

Solutions 500

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

Equilibrium 100

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

keq

(H2)2 (O

2)

(H2O)2

Equilibrium 200

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?

2MgO2 2MgO

keq

(2.0)2

(0.03)2 (0.02)2.2x105

Equilibrium 300

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.

Equilibrium 400

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)

Equilibrium 500

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)

Thermo 100

What does entropy measure?

The amount of chaos (disorder) in a system

Thermo 200

How much energy is needed to heat 164.5 g ice at -27.6oC to 0.00oC?

9,490 J

Thermo 300

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

GAS

Thermo 400

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 0.129 J/g°C)

q = mctq = (15.5g)(0.129 J/g°C)(172.9 °C)q = 346 J

Thermo 500

Calculate the H for this reaction:C2H4(g) + H2(g) C2H6(g)

(H f for C2H4(g) = 52.5 kJ/mol;

Hf for C2H6(g) = -84.7 kJ/mol)

( 84.7) (52.50) 137.2kJ /mol

Acids & Bases 100

When an acid reacts with a base, what two types of compounds are formed?

Salt and Water

Acids & Bases 200

If the [H+] in a solution is 1 x 10-1 mol/L, what is the [OH-]?

1x10-13mol/L

Acids & Bases 300

If the pH is 4, what is the concentration of hydrogen ion?

1x10-4M

Acids & Bases 400

What is an acid according to Arrhenius?

Gives off hydrogen ions in solution

Acids & Bases 500

What does a buffer do?

A buffer helps keep the pH of a solution stable

Nuclear 100 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

Nuclear 200 1. What particle is needed to complete

this nuclear reaction?

86

222Rn84

218Po ___

2

4

Nuclear 300

___2 10

21

5525 nHMn

What particle is needed to complete this reaction?

26

55Fe

Nuclear 400

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

Nuclear 500 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

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)

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