AP Chem unit 1

alpha particles

positively charged particles with four times the mass of a hydrogen atom

non-metals

elements that are usually dull in appearance, poor conductors of heat and electricity, gases at room temperature

alkaline earth metals

metallic elements which are harder than the alkali metals and less reactive

Uses of mass spectrometry

- identify unknown compounds
- Find relative abundance of each isotope of an element - Determine structural information

molecular formula

shows the types and numbers of atoms combined in a single molecule of a molecular compound

E(photon) =

hc/λ

E=

mc^2

continous spectrum

an emission spectrum that consists of a continuum of wavelengths.

standing wave

a wave that appears to stand in one place, even though it is really two waves passing through each other

Schrodinger wave equation

a description of how the electron matter wave varies with location and time around the nucleus of a hydrogen atom

ml

magnetic quantum number

subshell

the set of orbitals that have the same n and l values

nodal surfaces

an area of an orbital having zero electron probability

p orbitals

dumbbell shaped and directed along the x, y, and z axis

Aufbau principle

An electron occupies the lowest-energy orbital that can receive it

lanthanide series

the f-block elements from period 6 that follow the element lanthanum

main group elements

the p-block elements together with the s-block elements

What is electron shielding?

The reduction of the attractive force between a positively charged nucleus and its outermost electrons.

equation for electron affinity

X(g) + e- -> X-(g) + energy

electron affinity _______ down a group

decreases

quantum tunneling

when particles move through a barrier that they theoretically shouldn't be able to pass according to physics

de Broglie

Scientist who suggested that all moving particles had a wave motion associated with them

infrared radiation

causes molecular vibrations

purpose of Schrodinger's wave equation

determines orbital shapes

exceptions to the octet rule

B: likes to have 3 bonds and only 6 e's
P: likes to have 5 bonds and 10 e's
S: likes to have 6 bonds and 12 e's

How does the mass of an ion affect its deflection in a magnetic field?

The lighter the ion, the more it is deflected.

What determines the number of positive charges on an ion?

The number of electrons that were knocked off in the first stage.

atom

the basic unit of a chemical element.

nucleus

Center of an atom

mole

A group of atoms bonded together

molar mass

the mass of one mole of a substance

periodic table

A chart of the elements showing the repeating pattern of their properties

element symbol

One or two letters that represent element.

atomic number

the number of protons in the nucleus of an atom

Isotopes

Atoms of the same element that have different numbers of neutrons

mass spectrometry

a technique that separates particles according to their mass

Steps of mass spectrometer

1. Vaporization
2. Ionization
3. Acceleration
4. Deflection
5. Detection

nuclear atom

the modern concept of the atom as having a dense center of positive charge (the nucleus) and electrons moving around the outside

where are halogens located?

Group 17

Halogens

forms diatomic molecules

binary ionic compound

a two-element compound consisting of a cation and an anion

empricial formula

lowest whole number ratio of atoms in a compound

theoretical yield

the maximum amount of product that could be formed from given amounts of reactants

frequency symbol

V

scattered radiation

radiation deflected from its path during its passage through matter

l

angular momentum quantum number

T/F: p orbitals have positive and negative spaces

true

T/F: orbitals with the same n have different energy levels

false

polyelectronic atoms

an atom with more than one electron

first ionization energy

the energy required to remove the first electron from an atom

second ionization energy equation

X+(g) -> X2+(g) + e-

isoelectric

same electron configuration

electronegativity _______ across a period

increases

paramagnetic

Atom containing unpaired electrons and is consequently attracted by a magnet.

wave-particle duality

electrons and light can behave as both a wave and a particle

binding energy

The energy that holds the nucleus together

cation

A positively charged ion

electric force

the attraction or repulsion between electric charges

What is a noble gas shortcut?

A shorthand way to write electron configurations.

Zeffective equation

Atomic number - core electrons

What role do positive charges play in the deflection of ions?

The more positive charges on the ion, the more it gets deflected.

proton

positively charged particle

neutron

no charge

electron

negatively charged particle

Where are electrons located?

orbitals

where are protons and neutrons located?

nucleus

subatomic particles

protons, neutrons, electrons

atomic mass

The average mass of all the isotopes of an element

T/F: 2nd ionization energy is less than 1st first ionization energy

false

law of definite proportions

a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound

cathode ray tube

A Piece of Equipment used to discover the electron

gamma rays

Electromagnetic waves with the shortest wavelengths and highest frequencies

beta particles

high speed electrons

T/F: the nucleus of an atom is high density

true

covalent bonds

sharing of electrons

molecule

A group of atoms bonded together

structural formula

a formula that shows the arrangement of atoms in the molecule of a compound.

example of a structural formula

H-O-H

space-filling model

a model of a molecule showing the relative sizes of the atoms and their relative orientations

ball and stick model

a molecular model that distorts the sizes of atoms but shows bond relationships clearly

how is a cation formed?

losing electrons

how is an anion formed?

gaining electrons

ionic bonding

Chemical bonding that results from the electrical attraction between cations and anions

polyatomic ion

A charged group of covalently bonded atoms

metals

Elements that are good conductors of electric current and heat.

Where are the alkali metals located?

Group 1

Alkali metals

reactive, soft, silver, shiny, low density

where are the alkaline earth metals located

Group 2

diatomic molecule

a molecule that consists of two atoms of the same element

where are noble gases located?

Group 18

noble gases

normally gases, low chemical reactivity

Oxyanion

a polyatomic ion that contains oxygen

Avogadro's number

6.02 x 10^23

Combustion device

used to analyze substances for hydrogen and carbon

what is a combustion device used for?

helps determine the mass percent of each element in a compound

products

Ending materials in a chemical reaction.

reactants

A starting material in a chemical reaction

percent yield

the ratio of the actual yield to the theoretical yield expressed as a percent

wavelength

The distance between two corresponding parts of a wave

wavelength symbol

λ