Chapter 3- Bonding And Chemical Interactions Flashcards
Metals lose electrons to become what?
Cations. Positive Ions
Nonmetals gain electrons to become what?
Anions
Negative ions
Metals gain/lose electrons to become cations?
Lose
Nonmetals gain/lose electrons to become an ions?
Gain
Ionic bond
Bond form between atoms that have significantly different electronegativities.
Electrons are not shared in an ionic bond.
For an ionic bond to form what must the value of the difference in electronegativity be?
Greater than 1.7
Ionic bonds generally form between what types of elements on the periodic table?
Between a metal and a nonmetal
What are characteristics of compounds with ionic bonds?
Very high melting and boiling points, dissolve readily in water, good conductors of electricity, form a crystal lattice.
Covalent bond
Form when two or more atoms of similar electronegativities interact.
Sharing of electrons.
Two types of covalent bonds nonpolar and polar covalent bonds.
Characteristics of compounds with covalent bonds.
Lower melting and boiling points. Poor conductors of electricity. Weak intermolecular interactions.
Bond order
The number of shared electron pairs between two atoms
Bond order of a single double and triple bonds.
Single bond has a bond order of one. Double bond has a bond order of two. Triple one has a bond order of three.
Bond length
Average distance between two nuclei of atoms in a bond.
As the number of shared electrons increases the atoms are pulled closer together… this decreases bond length. 
Bond energy
The energy required to break a bond by separating its components into their isolated gaseous atomic states.
The greater the number of pairs of electrons shared between the atomic nuclei the more energy required to break the bonds holding atoms together.
Polarity
When two atoms have a relative difference in electronegativity… causes one atom to have a more positive charge and the other item to have a more negative charge.
When two or more atoms have a relative difference in electronegativity creating a dipole which group causes one atom to have a more positive charge and the other item to have a more negative charge.
Nonpolar covalent bond
When atoms that have identical or nearly identical electronegativity share electron pairs resulting and equal distribution of electrons.
No separation of charge across the bond.
What are the seven common diatomic molecules that exhibit nonpolar covalent bonds?
H2, N2, O2, F2, CL2, BR2, I2
Pneumonic for the seven diatomic molecules
He only calls because nobody freaking interested.
H2, N2, O2, F2, CL2, BR2, I2
Anybody between atoms with a difference in electronegativity less than what is considered non-polar?
Difference in electronegativity less than 0.5
Polar covalent bond
Atoms that differ moderately in their electronegativities share electrons unevenly.
Between 0.5 and 1.7.
Not strong enough to be classified as an ionic bond
p=qd
Equation used to calculate the dipole moment of a polar bond or polar molecule
What equation do you use to calculate the dipole moment of a polar bond or a polar molecule?
p=qd
p=dipole moment
q=magnitude of charge
d=displacement
Coordinate Covalent Bond
When both of the shared electrons originated on the same atom.
Lone pair of one atom attacks another atom with an unhybridized P orbital to form a bond.
Typically found in Lewis acid-base reactions.
Bonding versus non-bonding electrons
Bonding electrons are the electrons in the valance shell that are involved in a covalent bond.
Non-bonding electrons are the electrons in their valence shell that are not involved in the covalent bond.
Lewis structure
Shows the different possible ways in which atoms may be combined to form different compounds or resonance forms of a single compound.
When more than one arrangement can be made the arrangement that minimizes the numbered magnitude of formal charges is usually the most stable arrangement.
Neumonic for electronegative atoms
F O Cl N Br S H
Formula for formal charge
Formal charges equal to balance electrons minus non-bonding minus bonding electrons.
FC=VE-Dots-Sticks 
Formal charge
Used to determine if a Lewis structure is representative of the actual arrangement of atoms in a compound.
The arrangement that minimizes the formal charge is usually the most stable arrangement of the compound. 
What three rules help you determine the preferred Lewis structure
One. A Lewis structure was smaller no formal charges is preferred.
Two. A Lewis structure with less separation between opposite charges is preferred over a Lewis structure with large separation of opposite charges.
Three. A little structure where negative formal charges are placed on more electronegative atoms is more stable than one in which the negative formal charges are placed on less electronegative atoms.
Which elements are exceptions to the octet rule because they cannot or do not reach octets usually?
Hydrogen, helium, lithium, beryllium, boron.
Starting with which period of the periodic table do elements qualify to be exceptions for the octet rule?
Period three and beyond
VSPER theory
Valence shell electron pair repulsion theory.
The three dimensional arrangement of an atom surrounding a central atom is determined by the repulsions between bonding and non bonding electron pairs in The valence shell of the central atom these electron pairs arrangements as far apart as possible there by minimization repulsive forces. 
A molecule with two regions of electron density has what shape and what angle between its electron pairs?
Linear 180
A molecule with three regions of electron density has what shape and what angle between its electron pairs?
Trigonal planar 120
A molecule with four regions of electron density has what shape and what angle between its electron pairs?
Tetrahedral 109.5
A molecule with five regions of electron density has what shape and what angle between its electron pairs?
Trigonal bipyramidal 90,120,180
A molecule with six regions of electron density has what shape and what angle between its electron pairs?
Octahedral 90, 180
Electronic versus molecular geometry
Electronic geometry describes spatial arrangement of all pairs of electrons around the central atom.
Molecular geometry describes the spatial arrangement of only the bonding pairs of electrons
Coordination number
Number of atoms of surround and are bonded to the central atom contribute to the molecular geometry.
Between non-bonding and bonding electrons which exert more repulsion?
Non-bonding electrons exert more reposing than bonding pairs because they reside closer to the nucleus. Example between ammonia which has two non-bonding electrons in water that has four non-bonding electrons water has a smaller ideal bond angle.
107 vs 104.5
Are polar molecules contain what type of bonds?
Polar
Nonpolar molecules contain what types of bonds?
Nonpolar bonds, polar bonds and dipole moments that cancel each other out.
Intermolecular forces
Electrostatic attractions between molecules.
Significantly weaker than ionic and covalent bonds.
Between intermolecular forces, ionic bonds and covalent bonds rank them from decreasing strength
Ionic > Covalent > Intermolecular
London dispersion forces
The weakest interactions.
A type of intermolecular force.
Present in all atoms in molecules.
As the size of the atom or structure increases so does the corresponding London dispersion forces.
Dipole dipole interactions
Occur between oppositely charged ends of polar molecules.
Stronger than London forces.
Evident in solid and liquid phases but negligible and gas phases due to the distance between the particles.
Include hydrogen bonds
Hydrogen bonds
Specialized subset of dipole dipole interactions
involved in intra and intermolecular attraction.
When hydrogen bonds to either fluorine oxygen or nitrogen. 
Hydrogen bonded to fluorine oxygen or nitrogen is what type of bond?
Hydrogen bond. Type of intermolecular force.
Sigma bonds are the result of what type of overlap?
Head to head overlap of electron cloud densities
Pi bonds are the result of what type of overlap?
Overlap of two parallel electron cloud densities
Between Sigma and pi bonds which allows free rotation?
Sigma binds
