Test Chem
How does changing the electronegativity of the atoms affect the bond polarity?
Great the electronegativity, greeater the polarity
Hydrogen bonds
Only with N,O,F
Conductivity particles on molecular level
Particles have no charge
Dipole-Ion force
Add the H2O bonds, o's go to plus sign, h's to minus sign
How does changing the electronegativity of the atoms affect the bond character?
As you increase the electronegativity for atoms the bond character becomes more covalent (vice versa).
Dipole-dipole force
Boob looking this with infinity positive on left and negative on right
Explain the relative melting points of the two different types of solids. Explain the statement in terms of bonding occuring in ionic vs molecular solids.
Molecular substances have lower melting points and ionic substances have high melting points. Ionic substances have a stronger attraction because of their symmetry. Ionic does not have dipoles.
Dispersion force
More e' in the molecule, the higher the boiling/melting point
How does electron pair repulsion determind the molecular heometry?
The electrons do not attract, they repel. They spread out and create balanced repulsion between each pair. It is not possible to have them close together. For example, the trigonal planar forms a triangular shape which gives an equal distance.
How does electron density impact the boiling points of the materials? Explain the trend in boiling points by showing how electron density is related to van der waals forces. How do stronger intermolecular forces impact boiling points?
The higher the boiling point, the hugher the electron density. The boiling points' trend follows the dispersion force of van der waal. The stronger attraction the higher the boiling point.
Explain how the direction of the arrow in the bond dipole symbol relates to electron density and the partial charges
The more electronegativity difference the more dense the atom is. The closer electronegativities get to one another, the closer the densities.
Is there a relationship between the magnitude of the bond dipole and how the molecule is affected by the electric field?
The more electronegativity the atom contains, the more positive it will be and the faster it will move.
What happens to the molecule AB when it has a bond dipole and the electric field is turned on? Spin the molecule around several times and make observations. What if the bond dipole is zero?
The positive side of the molecule is attracted to the negative plate and vice versa. The dipole points to the positive plate. If the bond dipole is zero, neither atoms in the molecule attract to the positive or negative plates.
Do nonbonding pairs occupy more or less or the same amount of space as bonding pairs?
They occupy more space than bonding pairs
