CHem 111- Test 4- St. Thomas

Question 1

Atm–> torr–>psi

Answer 1

1.00 atm=760.0 torr= 14.7 psi

Question 2

Ideal gas law

Answer 2

PV=nRT

Question 3

what is R

Answer 3

0.08206 atm L/mol K

Question 4

STP

Answer 4

298K and 1.00 atm

Question 5

density (normal)

Answer 5

= Mass/volume

Question 6

mass=

Answer 6

= moles x molar mass

Question 7

density (special)

Answer 7

d= n x MM/nRT =P x MM/RT

Question 8

kinetic energy, constant temp

Answer 8

massive objects have lower average velocity

Question 9

kinetic energy (higher temperature)

Answer 9

objects have higher average velocity

Question 10

larger or more polar (kinetic energy)

Answer 10

they are sticker molecules and deviate from normal behavior

Question 11

another name for bonds

Answer 11

intrAmolecular forces,, hold atoms together

Question 12

inter molecular forces

Answer 12

hold molecules together

Question 13

3 types of intermolecular forces

Answer 13

london (dispersion) forces, dipole dipole forces, hydrogen bonding

Question 14

london (dispersion) forces

Answer 14

• between nonpolar molecules
• increase in streath with greater mass
• form temporary dipole
• weaker for smaller molecules

Question 15

dipole-dipole forces

Answer 15

• between polar molecules
• increase in strength with greater polarity
• form from permanent dipole
• intermediate strength

Question 16

hydrogen bonding

Answer 16

• between polar molecules with H bonded to O, N or F
• More H-bonds make a stronger force
• Strongest IMF for molecultes of a smililar size

Question 17

surface tension and viscosity

Answer 17

imcrease with increasing IMF strength

Question 18

boiling point

Answer 18

the temperature where the vapor pressure = atmospheric pressure

Question 19

Lower IMF means that…

Answer 19

• it is easier to separate molecules into gas phase
• there is a lower boiling point
• there is a higher vapor pressure

Question 20

Change in Hvap

Answer 20

energy required to vaporize given amount of liquid into gas

Question 21

total heat required equation

Answer 21

MCsΔT + ΔHfusn + MClΔT + ΔHvapn+M*CgΔT

M= mass, n = moles

Question 22

boiling point is at what pressure

Answer 22

1 atm

Question 23

crystalline

Answer 23

ordered, ionic and some covalent

Question 24

amorphous

Answer 24

not ordered, mostly covalent

Question 25

how are solids held together?

Answer 25

* Ionic solids * Metallic solids * Molecular solids * network solids

Question 26

ionic solid

Answer 26

held by ionic bonds

Question 27

metallic solids

Answer 27

held by metallic bonds

Question 28

molecular solid

Answer 28

held by IMFs- covalent molecultes (this is strong but weaker than covalent or ionic BONDS)

Question 29

network solids

Answer 29

held by covalent bonds

Question 30

melting point of a molecular solid is ____ than ionic or network

Answer 30

lower

Question 31

properties of metal

Answer 31

malleable (bendable) and conduct electricity

Question 32

what type of solid is diamon

Answer 32

network solid

Question 33

why do solutions form?

Answer 33

when energy of solution < energy of solute and solvent when energy of forces holding solvent + solute together < energy of forces holding together solute and solvent individually

Question 34

IMFs (this time, 6 of them)

Answer 34

1. london forces 2. dipole dipole 3. h bonding 4. ion dipole 5. ion induced dipole 6. dipole induced dipole

Question 35

ion dipole

Answer 35

strong force between an ion and a polar molecule

Question 36

ion- induced dipole

Answer 36

force between ion and non-polar molecule

Question 37

dipole-induced dipole

Answer 37

force between polar molecule and non-polar molecule

Question 38

what does like dissolves like mean

Answer 38

solutes will mostly dissolve in solvents that have same IMF acting on them (also salts (ionic) dissolve in H2O)

Question 39

electrolytes

Answer 39

solutions containing ions (conduct electricity)

Question 40

stong electrolytes

Answer 40

completely breaks apart to form ions when dissolved- forms strongly conductive solutions (ionic compounds + strong acids)

Question 41

weak electrolytes

Answer 41

partially breaks apart ti firn uibs wgeb dussikved- frs weakly conductive (weak acids + bases)

Question 42

non-electrolytes

Answer 42

does not form ions when dissolved- non conducting solutions (soluable covalent compounds)

Question 43

soluability of gases in water (temp)

Answer 43

higher temp= less gas dissolved

Question 44

soluability of gases in water (pressure)

Answer 44

higher pressure= more gas dissolved

Question 45

when are molecules stickier?

Answer 45

when they are larger or more polar

Question 46

rate of diffusion

Answer 46

the square root thing

Question 47

when will a gas behave most like an ideal gas?

Answer 47

at HIGH temp and LOW pressure