Chemistry 230 facts u need to know to pass the regents

STUDY GUIDE

Atoms are the _____ unit of matter

smallest

atoms consist of a ______ nucleus

central

The nuclei contain _____ and ______

Portons and Nuetrons

Electrons occupy regions around the nucleus called _____

Orbitals

Protons are ____ charged

Positively charged

Protons have a mass of ____ amu

1 amu

Nuetrons have no ______ (are Nuetral)

charge

Nuetrons have a mass of _____ amu

1 amu

Electons are _____ charged

Negativley

Electrons have an effective mass of ____ amu (1/1836 of a proton)

0 amu

The nucleus as a whole is _____ charged

positively

______ are atoms with the same atomic # but with diff. atomic masses (diff. # of nuetrons)

Isotopes

There are ____ common isotopes of Hydrogen

3

Protium (1p+,0n 0)

Hydrogen-1

Deuterium (1p+,1n 0)

Hydrogen-2

Tritium (1p+,2n 0)

Hydrogen-3

Tritium is ____ (decays by B emission)

Radioactive

________= the sum of protons and neutrons

Mass Number

_______ is the weighted avg. of all the isotopes of that element (based on their relative abundances in nature)

Atomic Mass

______ of the atom is commonly accepted as a simple model of an atom

Bohr´s Model

The energy levels are named _____ or ______

K,L,M,N,O,P etc and 1,2,3,4,5, etc

These energy levels are also known as ______

Principal quantum numbers

each orbital holds a ditinct # of _____ (2e-)

Electrons

Electrons give off distant colors when they return to their normal energy levels (_______) after they are energized ; characteristic ¨_______¨ are emitted as electrons move from high energy level to low energy levels

Ground State and Spectral Lines

The last/highest energy level with electrons in it is called the _______

Valence Shell

An atom´s ¨_____¨ is its nucleus and all energy levels execept the valence energy level

Kernal

The _______ of the elements is an organized chart of all known elements

Periodic Table

elements on the periodic chart are arrenged by _______ (increasing nuclear charge)

Atomic Number

Elements are classified as _________

metals, nonmetals, and metalloids.

Metalloids are elements that display properties of both ________

metals and nonmetals.

Elements can be grouped according to their ________

valence shell electron number.

Elements with 1, 2, and/or 3 valence shell electrons are ______

metals.

Elements with 5, 6, and/or 7 valence shell electrons are _______

nonmetals.

________ are elements along the “staircase” boundary between metals and nonmetals.

Metalloids

_______ are in Group 18 of the periodic chart.

Noble gases

Noble gases have 8 valence shell electrons (already satisfy the “______ Rule”) (except Helium, which has 2 valence electrons).

Octet Rule

Vertical ______ (columns) of elements display similar chemical properties.

Groups

Horizontal rows are called _____ ; properties change slowly from metallic to nonmetallic across a period.

periods

________ represents the number of occupied principal energy levels for a given element.

The period (row) number

________ is the closest distance to which one atom can approach another of the same type of atom.

Atomic radius

_______is the distance from the center of the nucleus to the outer valence shell of that atom (or, half the distance between two covalently bonded atoms of the same element).

Covalent radius