Transcript 7IMF physical props and polymers

Bonds, IMF, and
Physical Properties
How we can predict the
behavior of molecules!
Objectives
When given a molecule, determine the type of
bond that holds the atoms together and the type
of IMF that holds different molecules together.
To describe the characteristics of any molecule,
when given the type of bond
– MP/BP
– Physical State
– Conductivity
- Type of Particles
- Solubility
- Keywords
To compare and contrast a polymer and a
monomer
To identify what type of monomer makes up:
– Proteins
– Nucleic acids
- Starches
Metallic Compounds
Examples: Al, Cu, Fe
Types of atoms: cations in sea of electrons
Electrons are: In a community
IMF’s = metallic bonds
Strength of IMF Very strong
Physical state – all solids except Hg
Melting/Boiling Pts. – variable – depends on
charge and size
Solubility in water – Not soluble
Conductivity – conduct as solids or liquids
Keywords: ductile, malleable, electron sea
model, delocalized electrons
Ionic Compounds
Examples: NaCl, MgO
Types of atoms: Metal and Non-metal
– Groups 1-3 and trans metals are 1st element
Electrons are: Transferred or Exchanged
IMF’s = Ionic bonds
Strength of IMFs: Strongest
Physical state – crystalline solids, brittle
Melting/Boiling Pts. – very high
Solubility in water – most are soluble
Conductivity – conduct as liquids or when
dissolved in water.
Key words: electrostatic, lattice, brittle, hard
Polar Covalent Compounds
Examples: H2S, HCl, H2O
Types of atoms: usually 2 or more non-metals
(e-neg difference between 0.5 to 1.7)
Electrons are: unequally shared, causing areas
of partial charges
IMF’s = Dipole-Dipole and maybe Hydrogen
bonds if Hydrogen is present
Strength of IMFs: Mid range
Physical state – usually gases or liquids at room
temperature, but can be solid
– Depends on molecular weight (MW)
Melting/Boiling Pts. – low to medium
Solubility in water – most are soluble
Conductivity – Do not conduct
Non-Polar Covalent Compounds
Examples: O2, CH4, CO2
Types of atoms: 2 or more non-metals (both
non-metals are close together or have similar eneg)
Electrons are: Equally shared
IMF’s = Van Der Waals (Dispersion)
Strength of IMFs: Weakest
Physical state – usually gases at room
temperature, can be liquids, and rarely solids
– Depends on molecular weight (MW)
Melting/Boiling Pts. – very low to low
Solubility in water – Not soluble
Conductivity – poor to non conducting
Polymers
A polymer is a long, chain like molecule that is
made up of repeating units, called monomers.
Polymers are a specific type of covalent bond
Many important molecules necessary for life are
polymers.
– Proteins are made up of amino acids
– Starches are made up of sugars
– Nucleic acids are made up of sugar, nitrogenous
base, and phosphate group
Proteins
Add 1000s of individual amino acids → Proteins
Nucleic Acids
2 types of nucleic acids
• DNA
• RNA
Made up of repeating
monomers of
• Sugar
• Base
• Phosphate (PO4)
100s (sugar + nitrogenous base + PO4) → nucleic acid
Starches
Starches are sugars the
body uses to store energy.
Different starches have
different monomers
Starch: The glucose face
the same way
Cellulose: The glucose
alternate
Glycogen: The glucose
fold up
Add 1000s sugars → starch
Polymerization Animation