Chemistry Test #3

Front 1

What is Boyle's law?

Back 1

1. Pressure and Volume have an inverse relationship.
2. P=nRT/V
3. P1V1=P2V2

Front 2

What is Charle's Law?

Back 2

1. Volume and Temp are directly related.
2. At absolute zero, an ideal gas would disappear, but doesn't actually happen.
3. V=(nR/P)T
4. V1/T1=V2/T2

Front 3

What is Avogadro's Law?

Back 3

1. V=n(RT/P)
2. Volume and amount (n) are directly related.
3. V1/n1=V2/n2

Front 4

What is Gay-Lassac's Law?

Back 4

1. Pressure and temp are directly related.
2. P=(nRT/V)
3. P1/T1=P2/T2

Front 5

What unit does the temp need to be in for gases?

Back 5

1. KELVINS

Front 6

Gas characteristics?

Back 6

1. Free space in gases
2. Gases can expand infinitely
3. Gases occupy containers uniformly and completely.
4. Diffuse and mix rapidly/randomly
5. Most disordered phase of matter

Front 7

What are the ideal gas laws?

Back 7

1. Particles in constant, random motion.
2. Pressure arises from collisions with container walls.
3. No attraction/repulsion forces
4. Volume of gas particles is negligible
5. All gases have same kinetic energy at same temp.

Front 8

How many liters in 1 mol of a when it goes to a gas?

Back 8

1. 22.4 liters

Front 9

What is pressure?

Back 9

1. Force exerted per unit area by gas molecules as they strike the surfaces around them.

Front 10

Equation for pressure?

Back 10

1. Pressure = Force/Area

Front 11

What is a barometer?

Back 11

1. Evacuated glass tube whose tip is submerged in a pool of mercury.

Front 12

1mmHg = _____

Back 12

1. 1 torr

Front 13

What is an atmosphere (atm)?

Back 13

1. average pressure at sea level.
2. 1 atm = 760 mmHg

Front 14

SI unit of pressure?

Back 14

1. Pascal (Pa)
2. 1 N/m2

Front 15

Manometer?

Back 15

1. One end of tube is open to atmospheric pressure and other is attached to a flask containing gas sample.
2. If atmospheric pressure is same as gas pressure, levels of mercury will be same.
3. P=h*density*g
3. If pressure of the gas is greater than atmosphere, then level of mercury on left side is higher.

Front 16

What is the ideal gas constant?

Back 16

1. .08206 L*atm/mol*K

Front 17

What is the Ideal Gas Law equation?

Back 17

1. PV=nRT

Front 18

What is standard temp and pressure (STP)

Back 18

1. T = 273 K
2. P = 1.00 atm

Front 19

What is the molar volume?

Back 19

1. Volume occupied by one mole of gas under STP.
2. 22.4 Liters

Front 20

Is the density of a gas directly proportional to molar mass or inversly proportional? What is the equation?

Back 20

1. Directly proportional
2. d= PM/RT

Front 21

What is partial pressure?

Back 21

1. Pressure due to any individual component in a gas mixture.

Front 22

What is Dalton's Law of Partial Pressures?

Back 22

1. Sum of partial pressures of the components in a gas mixture must equal the total pressure.

Front 23

Mole fraction (XA)

Back 23

1. Number of moles of a component in a mixture divided by the total number of moles in the mixture.

Front 24

What is hypoxia?

Back 24

1. Oxygen starvation
2. Occurs when PO2 drops below .1 atm.
3. Why climbers on Everest need O2 tanks.

Front 25

What is nitrogen narcosis?

Back 25

1. When PN2 goes above 4 atm.
2. Rapture of the deep
3. Feel drunk, can drown

Front 26

What is oxygen toxicity?

Back 26

1. When PO2 increases above 1.4 atm.
2. Results in muscle twitching, tunnel vision, convulsions.

Front 27

What is vapor pressure?

Back 27

1. Partial pressure of water in a mixture.
2. Depends on the temperature.
3. Vapor pressure increases with increasing temperature because higher temps cause more water molecules to evaporate.

Front 28

What is diffusion?

Back 28

1. Gas molecules spread out in response to a concentration gradient - Diffusion.

Front 29

What is effusion?

Back 29

1. Gas escapes from a container into a vacuum through a small hole.

Front 30

What is the mean free path?

Back 30

1. Average distance that a molecule travels between collisions.

Front 31

What is Graham's Law of Effusion?

Back 31

1. Ratio of effusion rates of two different gases.
2. rate A/rate B= Square root (MB/MA)

Front 32

What is the Van Der Waals Equation? What does it do to the former ideal gas law equation?

Back 32

1. Adds a correction to it to include the intermolecular forces and particle volume.
2. [P+a(n/v)^2]X[V-nb]=nRT

Front 33

What is thermochemistry?

Back 33

1. Study of temp and heat flow that occurs in chemical reactions.

Front 34

What is energy?

Back 34

1. Capacity to do work

Front 35

What is work (w)?

Back 35

1. Force acting over a distance.
2. W= Pressure X change in Volume.

Front 36

What is heat (q)?

Back 36

1. Flow of energy caused by a temperature difference.

Front 37

Kinetic energy and potential energy?

Back 37

1. Energy in motion - Kinetic.
2. Energy due to position or composition - Potential.

Front 38

Thermal energy...

Back 38

1. Form of kinetic energy
2. Molecules in motion - more vibrations = more heat released

Front 39

Chemical energy...

Back 39

1. Form of potential energy.
2. BONDS!!
3. When a bond breaks, energy is given off in form of heat.

Front 40

The system...

Back 40

1. This is what is being examined.
2. Chemical reaction for example.

Front 41

The surroundings...

Back 41

1. Everything that is not the system, with which the system can exchange energy.

Front 42

System can ______ energy to surrounds or ______ energy from surroundings.

Back 42

1. Lose
2. Gain

Front 43

How many Joules are in 1 calorie?

Back 43

1. 4.18 Joules (J)

Front 44

What is the first law of thermodynamics?

Back 44

1. Total energy of the universe is constant.
2. When energy is converted from one form to another, some is "lost" to the surroundings as heat.

Front 45

What is state function?

Back 45

1. Property of a system whose value does not depend on how the system the system arrived at that state.
2. Climbing mountain - whether go straight up or weave your way up, still climb to top distance.

Front 46

Internal energy equals....

Back 46

1. Kinetic Energy + Potential Energy

Front 47

Energy change is a _________.

Back 47

1. State function

Front 48

What is the energy change equation?

Back 48

1. Change in energy= Final energy - Initial energy.

Front 49

If change energy is negative value, then....

Back 49

1. Heat flowing out of the system.

Front 50

If change energy is positive value , then...

Back 50

1. Heat flows from the surroundings into system.

Front 51

If something feels warm, then heat is ____________.

Back 51

1. Coming out of the system into the surroundings.

Front 52

Thermal Equilibrium...

Back 52

1. A point where there is no additional net transfer of heat between system and surroundings.

Front 53

Heat Capacity (C)

Back 53

1. Quantity of heat required to change its temperature by 1 degree Celcius.
2. J/C

Front 54

Specific heat capacity (Cs)

Back 54

1. Measure of intrinsic capacity of a substance to absorb heat.
2. J/g*degreesC

Front 55

Molar Heat capacity...

Back 55

1. Amount of heat required to raise the temp of 1 mole of a substance by 1 degree Celcius.

Front 56

Are molar heat and specific heat capacity intensive or extensive properties?

Back 56

1. INTENSIVE - depend on substance not the amount.

Front 57

What has the highest specific heat capacity of all substance?

Back 57

1. Water

Front 58

Pressure-Volume work...

Back 58

1. Occurs when the force is a result of a volume change against an external pressure.

Front 59

Calorimetry...

Back 59

1. thermal energy exchanged between the reaction/system and the surroundings is measured by observing the change in temperature of the surroundings.

Front 60

Bomb calorimeter...

Back 60

1. Sealed lid forces reaction to occur at constant volume.
2. "Bomb" is ignited in the water and heat given off into surroundings is measured.
3. qcal=Ccal X delta T
4. qcal= -qrxn
4. Measures COMBUSTION reactions

Front 61

What is enthalpy?

Back 61

1. Sum of a system's internal energy and the product of its pressure and volume.
2. State function
3. H= E + PV

Front 62

What is the difference between endothermic and exothermic?

Back 62

1. Endothermic - positive delta H, heat flows into system. Feels cold.
2. Exothermic - negative delta H, heat flows out of system. Gives off heat, feels hot!

Front 63

Enthalpy of reaction is an ________ property?

Back 63

1. EXTENSIVE - depends on amount.
2. Amount of heat generated or absorbed depends on amounts that react.

Front 64

What does a coffee-cup calorimeter do?

Back 64

1. used to measure enthalphy changes for chemical reactions in solution.

Front 65

If a chemical equation is multiplied by a factor, what happens to the Delta Hrxn

Back 65

1. It is multiplied by the same factor.

Front 66

If a chemical equation is reversed what happens to the Delta Hrxn?

Back 66

1. It changes sign.

Front 67

If a chemical reaction can be expressed as the sum of a series of steps, then Delta Hrxn for the overall equation is..........

Back 67

1. The sum of the heats of reactions for each step.
2. Also known as Hess's Law!

Front 68

Review pg. 262, Standard State, Standard Enthalpy change, Standard Enthalpy of formation.

Back 68

1

Front 69

One letter designation for energy, in the form of heat that LEAVES a system...

Back 69

1. -q

Front 70

One letter designation for pressure-volume work that LEAVES a system...

Back 70

1. -w

Front 71

One calorie (cal) or 4.184 Joules (J) is the amount of heat required to increase the temperature of ____g of water a total of _____degree Celcius

Back 71

1. 1, 1

Front 72

Heat exchange reactions are performed in an instrument known as a _______________.

Back 72

1. Calorimeter

Front 73

What is a "state function?"

Back 73

1. Value in a system that does not depend upon the methods used to get to that value.
2. Internal Energy is an example.

Front 74

Why is chemical energy, potential energy?

Back 74

1. Due to bonds.
2. When bonds are broken energy is given off as heat.
3. The bonds hold the potential of energy if they are broken.

Front 75

In a system, what is the equation that describes energy change?

Back 75

1. Delta E = E final - E initial.

Front 76

Mathematically, how does one describe the total internal energy of substance?

Back 76

1. Internal = PE + KE.

Front 77

When energy is converted from one form to another, what always occurs?

Back 77

1. Heat is given off.

Front 78

What is the law of conservation of energy compared to the 1st law of thermodynamics?

Back 78

1. Law of conservation of energy says that energy cannot be created nor destroyed.
2. The 1st law of thermodynamics says that the total energy in the universe is constant.

Front 79

What is heat?

Back 79

1. Flow of energy caused by temperature difference.
2. Transfer of thermal energy.

Front 80

Why is thermal energy also kinetic energy?

Back 80

1. Due to the motion of particles and how they give off heat.

Front 81

Greater specific heat = _____ energy required to raise temp of substance.

Back 81

1. More energy

Front 82

What should you remember when calculating Root Mean Square Velocity?

Back 82

1. Remember R = 8.314
2. Use kg for M
3. square root (3RT/M)

Front 83

If using the w=-PV, remember what at the end of the equation?

Back 83

1. To take answer in L*atm X 101.3 to get J.

Front 84

What is heat of formation?

Back 84

1. heat/energy required to make a compound starting with atoms in elemental state.