Solid, liquid gas Flashcards
Causes of Non- ideality of gas
Vanderwall studied
1. No forces of attraction
2. Volume of gas compared to vessel negligible
intermolecular forces
- Dipole-dipole
- Ion-dipole
- dipole-induced dipole
- id-id
- hydrogen bonding
intramolecular(strong)forces
Ionic, covalent bonding
strength of intermolecular forces depends on
polarity. bigger size molecule has stronger imf
dipole dipole
PRESENT IN POLAR MOLECULES
difference in electronegativity of a molecule results in one end being partial positive one being partial negative. e.g HCL
strength of dipole dipole depends on
size of molecules and e.n difference
dipole-induced dipole [DEBYE forces]
{polar-nonpolar}
positive end of a polar molecule attracts mobile e- of nonpolar molecule.both molecules become dipoles
instantaneous-induced dipole [LONDON]
attraction between NONPOLAR molecules(weakest force)
momentary force created between instantaneous dipole and induced dipole. (short lived attraction as e- keeps on moving)
>actually present in all molecules
factors affecting london forces
- size of electronic cloud(extent of distribution)
2.number of atoms(atomic size) increase b.p and forces
ion-dipole forces
ion-polar.
hydration of ions.e.g Na+ and H2O, Cl- and H2O
order of strength of intermolecular forces
H-bonding>dipole-dipole>Debye forces>London forces
hydrogen bonding
partial positive hydrogen and partial negative HIGHLY NEGATIVE such as F, O, N.
20 timmes weaker than a covalent bond
solubility of hydrogen bonded molecules
compounds with hydrogen bond are soluble in hydrogen compounds such as
carboxylic acids and alcohols being soluble in water and hydrocarbons insoluble due to being nonpolar and polar nature of water
hydrogen bonding in biological compounds
coiling of amino acids form hydrogen bonds in hair, muscles and silk.
>DNA nucleotides have hydrogen bonds between them
adhesive action of paints, dyes, glues is due to which type of bonding
Hydrogen bonding
vapour pressure and values of compounds
pressure exerted by vapours of liquid in equilibrium with the liquid at a given temperature.
NAME OF COMP VAPOUR
PRESSURE AT 20C
isopentene 580 torr
ethyl ether 442.2
chlorofoam 170
ccl4 87
water 17.54
glycerol 0.00016
factors affecting vapour pressure
1. temperature
2. amount of liquid
3. intermolecular forces
4. density/ molecular mass
5. volume of container
6. surface area
- direct
- NOT DEPENDANT
- inverse
- inverse
5.NOT DEPENDANT
6.NOT DEPENDANT
method of determining vapour pressure
manometric method
molar heat of fusion
amount of heat absorbed when 1 mol of a solid melts into liquid form at melting point and 1atm
molar heat of vapourization
amount of heat absorbed when 1 mol of a liquid changed into vapours at boiling point and 1 atm
water’s—-> 40.6 KJmol-1
Molar heat of sublimation
amount of heat absorbed when 1 mol of solid sublimes into vapours at a particular temperatue and 1 atm
true or false.
heat of s> heat of v> heat of fusion
TRUE.
sublimation greater than vapourisation, which is grreater than fusion
uses of liquid crystals
temperature sensors
skin thermograhy for veins, arteries infectioons and tumours
TV displays
crystalline solids and amorphous
made up of a unit cell and have three dimensional arrangement
e.g cu, iron, ice, diamnd.
shapeless and no regular arrangement.
e.g glass,plastic,rubbber,glue,wood.
have no sharp melting points.glass can be blown into diff shapes.
you can make an amorphous solid from crystalline by melting and rapid cooling
crystals and their classification.[table]
1. cubic
2. tetragonal
3. orthorhombic
4. monoclinic
5. hexagonal
6. rhombohedral
7. triclinic
axes angles examples
1. a=b=c all 90 Fe,Cu,Ag,Au,NaCl
- a=b=/c all90 NH4br
- a=/b=/c all 90 iodine, sulphur
- a=/b=/c a=90,B=/90 sugar, na2so4
- a=b=/c a=B=90, y=120 graphite
- a=b=c a=B>90 Al2O3
- a=/b=/c no angle 90 K2Cr2O7
classification of solids.(crystalline)
with properties of ionic solids.
there are four types;
ionic,covalent,metallic and molecular
ionic solids;
>high mp/bp
>high density
>non conductor in solid. but conduct in molten or liquid
>isomorphism and polymorphism
>fast reactions
structure of NaCl
face centered cube.
coordination number 6.
each Na+ is surrounded by 6 Cl- and vice versa.
Formula unit: 4 NaCl
.each Cl- at corner is shared by 8 unit cells, so 8Cl- x 1/8= 1Cl-
.each Cl- faces 6 and shared by 2 unit cells so,
6Cl- x1/2= 3Cl-
total= 4
Anisotropic properties
Anisotropy; Direction dependant
- refractive index
- co efficient of thermal expansion
- electric conductivity
- thermal conductivity
