Physical science test 10 (13-14)

the organized study of the composition and interactions of matter

Chemistry

the foundation for the understanding of matter

atomic theory of matter (proposed by Dalton)

tiny particles that compose all matter

atoms

substances composed of a single type of atom

elements

composed of atoms of two or more elements bonded together

compounds

a unique abbreviation given to elements that is typically based on its common or Latin name

chemical symbol

atoms are composed of still smaller particles of matter called _______

subatomic particles

the dense central core of an atom

nucleus

part of an atom that carries a positive electric charge

proton

part of an atom that is neutral (no electric charge)

neutron

the number of protons in the nucleus

atomic number

atoms that are the same element but have different numbers of neutrons

isotopes

small particles that make up protons and neutrons

quarks

part of an atom that carries a negative electric charge

electron

concentric layers that surround the nucleus

electron shells

atom that has an electric charge because of losing or gaining electrons

ion

negative ions

anions

positive ions

cations

the total number of protons and neutrons in the nucleus

mass number

the average mass of all the neutral isotopes of an element

average atomic mass

the masses of atoms are usually measured in ___

atomic mass units (u)

states that tiny particles like electrons do not absorb or release energy in a smooth flow

quantum theory

regions in which electrons move unpredictably

orbitals

the most familiar model of the atom

Bohr model

model of the atom that shows electrons have characteristics of both particles and waves

wave-mechanical model

states that it is impossible to measure both the position and velocity of an electron with certainty

heisenberg uncertainty principle

a model of the atom that interprets the mathematical equations of the wave-mechanical model representing the probability of finding an electron at a given point

electron-could model

a set of numbers that mathematically represent the overall motion of an electron

quantum numbers

says that no two electrons in an atom can have the same four quantum numbers

pauli exclusion principle

the length of time required for one-half of the original substance to decay into a new substance

half-life

radioactive decay that occurs when a neutron in an atom’s nucleus changes into a proton, emitting an electron

beta decay

type of decay that increases the atomic number by one

beta decay

radioactive decay that occurs when an unstable atom ejects a clump of two protons and two neutrons

alpha decay

radioactive decay that occurs when an excited nucleus releases energy without a change in the number of protons or neutrons

gamma decay

type of decay that releases energy without a change in the number of protons or neutrons

gamma decay

the process whereby a heavy nucleus is split into several pieces by bombarding it with neutrons

nuclear fission

device that initiates an uncontrolled chain reaction

atomic bomb

a nuclear reactor that recycles spent nuclear fuel to produce more than it uses

breeder reactor

_____ initiates a controlled reaction

nuclear reactor

a device that harnesses controlled fission to produce useful energy

nuclear reactor

chain reaction cannot occur unless there is a certain amount of fissionable material present, called the _______

critical mass

the process of combining two nuclei to form a heavier nucleus and thereby releasing energy

nuclear fusion

a weapon that uses nuclear fusion to release a tremendous amount of energy

hydrogen bomb

the electrons in the outer shell of an atom

valence electrons

states that most atoms tend to react to obtain eight electrons in their valence shell

octet rule

states that elements show regular and repeating properties when they are arranged by their increasing atomic numbers

periodic law

table of the elements arranged by atomic number and number of valence electrons

periodic table of elements

1. a row of the periodic table

2. a column of the periodic table

1. period

2. group

elements in groups 1,2, and 13-18

main-group elements

the left side of the periodic table is ______

metals

the middle of the periodic table is _______

semimetals

the right side of the periodic table is ______

nonmetals

elements in group 17

halogens

elements in group 2

alkaline earth metals

elements in group 1

alkali metals

elements in group 16

chalcogens

elements in group 18

noble gases

a basic constituent of all living things

carbon

most abundant element in the body

oxygen

second most abundant element in the human body

carbon

groups of two or more atoms linked by chemical bonds to form distinct units

molecules

a substance that has the same physical properties throughout and consists of only one type of atom

pure substance

a homogeneous mixture

solution

composed of several pure substances that are physically mixed but not chemically united

mixture

substance doing the dissolving

solvent

substance being dissolved

solute

mixture containing tiny suspended clumps or particles

colloid

the appearance of a blue-tinged milky or cloudy effect within a colloid when a light shines through it

tyndall effect

molecules and compounds are composed of two or more atoms linked together by attractive forces called ______

chemical bonds

a chemical bond resulting from the sharing of valence electrons between atoms

covalent bond

occurs when two atoms share a single pair of electrons

single bond

occurs when two atoms share two pairs of electrons

double bond

occurs when two atoms share three pairs of electrons

triple bond

a diagram showing the locations of all the atoms and valence electrons

lewis structure

Al

aluminum

Ar

argon

As

Arsenic

Ba

Barium

B

Boron

Ca

Calcium

C

Carbon

Cl

Chlorine

Cu

copper

Au

gold

He

Helium

H

Hrdrogen

I

idodine

Fe

iron

Kr

Krypton

Pb

lead

Mg

magnesium

Hg

mercury

Ne

neon

Ni

nickel

N

nitrogen

O

Oxygen

P

phosphorus

K

potassium

Ra

radium

Rn

Radon