Principles of Chemistry - Module 2

Frequency is higher if….

The number of waves is greater.

The higher the frequency…

The higher the energy.

What is amplitude?

The height of the waves.

Number of photons=

total energy/energy per photon

Atomic Radius increases…

To the left and down.

Ionization energy increases…

To the right and up. (EXCEPT for elements with a full s or half-filled P sheild)

For largest ionic radius….

negative charges are greater than positive charges.

In electron pair geometry…

you count lone pairs as another bond.

Electronegativity increases…

to the right and up.

An element can only be bent if…

it has lone pairs.

A compound is polar if…

it is not symmetrical.

A compound is non-polar if…

it is symmetrical.

Equation for the energy of a mole of photons…

E=Nhc/λ , where N is avogadro’s number.

Absorbtion occurs when…

an electron moves to a higher energy level.

Emission occurs when…

An electron moves to a lower energy level.

For isoelectronic elements…

atomic number=number of electrons, then you add an electron for every negative charge and subtract an electron for every positive charge.

Bonds are more polar when…

they are closer on the periodic table.

A difference of what indicates that the bond is polar.

0.5 or greater.

What is the bond angle for a linear molecule.

180 degrees

What is the bond angle for a trigonal planar molecule?

120 degrees

What is the bond angle for a bent (trigonal planar) molecule?

< 120 degrees

What is the bond angle for a tetrahedral molecule?

109.5 degrees

What is the bond angle for a trigonal pyramidal molecule?

< 109.5 degrees

What is the bond angle for a bent (tetrahedral) molecule?

< 109 degrees

What is a ketone? (CetOne)

An O double bonded to a C.

What is an aldehyde? (aldeHyde)

An O double bonded to a C that is bonded to an H.

What is a carboxylic acid?

An O double bonded to a C bonded to an O bonded to a H.

What is an amide?

An O double bonded to a C bonded to an N bonded to 2 H(or R).

What is an ether? (ether=Other)

An O bonded to 2 C(or R)

What is an amine? (amiNe)

An N bonded to 3 molecules (or H).

What is an phenyl?

A hexagon of C’s bonded to H’s.

What is an alochol? (alocHOl)

An O bonded to an H and another element(R).

What is the formula to find frequency?

V=c/λ (in m)

What is the conversion rate for nm to m?

1 nm = 1e-9 m

What can’t you know about electron clouds?

You cannot determine the precise location of the electrons.

What can’t you know about quantum mechanical models?

It does not provide the precise path taken by an electron.

What are the units of frequency?

s^-1 or Hz

How many joules are in 1 kJ?

1000 J = 1 kJ

In potential energy/distance graphs, the stronger bond has…

A deeper well.

Delocalization means…

The electron cloud is more spread out.