Phases

Question 1

Ideal gases have what types of intermolecular forces?

Answer 1

No IMF’s

Question 2

Decreasing order of IMF’s

Answer 2

Solids -> liquids -> gases

Question 3

Condensation reaction

Answer 3

Gas to liquid

Question 4

Fusion reaction

Answer 4

Solid -> liquid (melting)

Question 5

Sublimination

Answer 5

Solid -> gas

Question 6

Deposition

Answer 6

Gas -> solid

Question 7

What happens when heat is absorbed?

Answer 7

Internal KE increases, entropy increases

Question 8

What is the triple point?

Answer 8

The temperature and pressure where all three phases coexist

Question 9

What is the critical point?

Answer 9

The temperature and pressure above which the difference between liquids and gases is no longer distinct

Question 10

What happens to the freezing and melting point of ice as pressure increases?

Answer 10

The freezing and melting point decrease

Question 11

Heart energy to change phase

Answer 11

q = n∇H

Units are in kJ

Question 12

Heat for temperature change

Answer 12

q = mc∇ T

m = mass (Units are in J)

Question 13

What effect does external pressure have on vapor pressure?

Answer 13

External pressure has no effect on vapor pressure

Question 14

Boiling point is where

Answer 14

Vapor pressure = Atmospheric pressure

Question 15

What is a solution?

Answer 15

A homogeneous mixture of two or more substances

Question 16

What are the relative quantities of solutes and solvents?

Answer 16

Solutes are normally present in smaller quantities

Question 17

How do strong/weak/non- electrolytes dissociate in water?

Answer 17

Strong electrolytes dissociate completely

Weak electrolytes partially dissociate

Non-electrolytes don’t dissociate

Question 18

Vant Hoff factor (i)

Answer 18

The # of particles per mole of a substance

Question 19

What is the Vant Hoff factor of sugar (C₆H₁₂O₆), NaCl, Ca(NO₃)₂, and HF respectively

Answer 19

Sugar = 1, it won’t dissociate in water

NaCl = 2

Ca(NO₃)₂ = 3

HF = 1 < i < 2

Question 20

Electrolyte process of dissociation

Answer 20

Agitation (endothermic) → Dissociation (endothermic) → Solvation (exothermic)

Dissociation is net exothermic

Question 21

Polar non-electrolytes dissolving process

Answer 21

Agitation → solvation

Question 22

Nonpolar non-electrolytes

Answer 22

Agitation

Question 23

What is solubility?

Answer 23

The amount of substance that can dissolve in a solvent at a specific temperature

Changes in temperature alter solubility

Question 24

What are the relative concentrations of an unsaturated solution?

Answer 24

[solute] < solubility

Additional solute will dissolve

Question 25

What are the relative concentrations of a **saturated solution?**

Answer 25

[solute] = solubility No additional solute will dissolve

Question 26

What are the relative concentrations of a **supersaturated solution?**

Answer 26

[solute] \> solubility Additional solute causes excess to precipitate

Question 27

What are the solubility rules of solids and liquids in water?

Answer 27

Solubility is proportional to temperature Solubility is not affected by pressure

Question 28

What are the solubility rules of a gas in water?

Answer 28

Solubility is indirectly proportional to temperature ## Footnote **Solubility is proportional to temperature**

Question 29

What electrolytes are always soluble in water? (6 items)

Answer 29

Alkali metals Hydrogen Ammonium (NH₄⁺) Nitrate (NO₃^-) Acetate (CH₃COO^-) Perchlorate (ClO₄^-)

Question 30

What electrolytes are usually insoluble in water? (6 items)

Answer 30

Silver Lead Mercury Carbonate (CO₃^2-) Phosphate (PO₄^3-) Sulfur

Question 31

What happens when you pair an insoluble electrolyte with a soluble electrolyte?

Answer 31

The substance is soluble in water

Question 32

Where would dissolved gas be highest in a shallow body of water?

Answer 32

The bottom

Question 33

How would you increase the solubility of sugar in water?

Answer 33

The substance is a solid Increase the temperature

Question 34

What are the components of the kinetic molecular theory of gases? (4 things)

Answer 34

An ideal gas has **zero IMF's** An ideal gas has **particles of negligible mass** (Helium) An ideal gas has an average **kinetic energy proportional to temperature** Ideal gas is favored at **high temperature and low pressure because it minimizes the interactions of the particles**

Question 35

What are the 4 pressure conversions?

Answer 35

1 atm = 101,000 Pa = 760 mmHg = 760 torr

Question 36

What are the volume equivalents?

Answer 36

1 L = .001 m³ = 1,000 mL = 1,000 cm³

Question 37

What are the conditions at STP?

Answer 37

0 degrees C (273 K) and 1 atm

Question 38

What are the **standard state conditions?**

Answer 38

25 degrees C ( 298 K), 1 atm

Question 39

What is the **combined gas law?**

Answer 39

P₁V₁ / T₁ = P₂V₂ / T₂

Question 40

How does pressure relate to volume?

Answer 40

Pressure is inversely proportional to volume

Question 41

How does Temperature relate to volume?

Answer 41

Temperature is proportional to volume

Question 42

How does temperature relate to pressure?

Answer 42

Temperature is proportional to pressure

Question 43

If the pressure and volume of a 2 mole sample of Helium is doubled, what is the new temperature if the initial temperature is 27 degrees C

Answer 43

\*Plug in simple numbers P₁V₁ / T₁ = P₂V₂ / T_{2 1 atm} * _{1 L / 300 K = 2 atm} * _{* 2 L / T T = 1200 K}

Question 44

What is Avogadro's Law

Answer 44

Volume is proportional to the number of moles

Question 45

What is the volume of NH3 made from 3 L N and 3 L H at STP? N₂ + 3 H₂ = 2N₂H₃

Answer 45

Take the number of moles of the limiting reagent and multiply if by the ratio of that reagent to the product 3 moles H₂ x 2 mol NH₃ / 3 mol H₂ = 2 mols NH₃

Question 46

What is the ideal gas law?

Answer 46

PV = nRT R = 0.08 L

Question 47

If given the number of moles near STP, how would you most simply find the volume?

Answer 47

V = 22.4 L/mol near STP 22.4 x # moles

Question 48

How do pressure and volume of ideal gases compare to real gases?

Answer 48

P_ideal \> P_real V_Ideal \> V_real

Question 49

What is the **Real Gas Law?**

Answer 49

(P + n²/V²\*a) (V - nb) = nRT

Question 50

Partial pressure equation and mole fraction equation

Answer 50

P_a = X_a\*P_total X_a= n_a/n_total

Question 51

What is Graham's law? (rate of diffusion)

Answer 51

The rate of diffusion (v) is inversely proportional to molecular weight v₁/v₂ = Square root of (mw₂/mw₁)