Imaging 1 Ch 3 book

four original substances

earth water air fire

four basic essences

wet

dry

hot

cold

greek atom meaning

indivisible to describe the smallest part of the four substances

a not + temon cut

currently how many elements are there ?

118

92 natural

26 artificial

an atom is the

smallest particle of matter that has properties of an element

subatomic particles definition

particles that are smaller than an atom

what did john dalton do?

published a book summarizing his experiments showing elements could be classified according to intergral values of atomic mass

dalton atom hook and eye

who was dmetri mendeleev?

russian scholar who created the periodic table of elements

blocks of the periodic table of elements

the superscript is

atomic number

blocks of the periodic table of elements

the subscript is the

elemental mass

each block on the periodic table of elements represents a

element

all elements in the same group/ column

react chemically similar and have similar physical properties

except for hydrogen the elements in group 1 are the

alkali metals

alkali metals definition

soft metals that combine with oxygen and react violently with water

elements of group 7 are called

halogens

halogens defintion

easily vaporized

combine with metals to form water soluble salts

group 8 elements are called the

noble gases

noble gases are

highly resistant to reaction with other elements

elemental groupings are determined by

placement of electrons in each atom

what did JJ thomson conclude

electrons were part of an atom

Ernest Ruthford did what

introduced the nuclear model

nucleus

center of the atom

small dense positively charged center surrounded by a negative cloud of electrons

what is bohrs model like (example)

a mini solar system

what is bohrs atom

electrons revolve around the nucleus in energy levels

quantum chromodynamics

in a normal atom the number of the

number of electrons is equal to the number of positive charges in the nucleus

more than _____ subatomic particles have been detected and described by physicists working with particle accelerators

100

____ (_____ and _____) are composed of quarks that are held together by gluons

nucleons

protons

neutrons

3 primary constituents of an atom

electron

proton

neutron

fundamental particles of atoms

protons

neutrons

electrons

when the atom is viewed as a mini solar system what are the planets and the sun?

sun- nucleus

planets-electrons

the arrangement of electrons around the nucleus determines

which atoms interact

how much electrical charge do electrons carry

1 unit

electron mass

9.1 × 10^-31 kg

atomic mass units

amu

atomic particle mass

1 atomic mass is equal to

1/12 the mass of carbon 12 atom

atomic mass numbers are used when

precision is not neccessary

what is a nucleon

particles of a nucleus - protons and neutrons

mass of a proton

1.673 × 10^-27

mass of a neutron

1.675 × 10^-27

atomic mass number of a proton or neutron is

1

difference between protons and neutrons

proton - 1 unit positive charge

neutron- NO charge neutral

an atom is actually mostly just

empty space

the nucleus of an atom contains most of the

atoms mass

the number of protons determines the

chemical behavior of the atom

chemical element

what do eletron shells tell us

reveals how it reacts and combines with other atoms to form molecules

isotopes definition

atoms that have the SAME number of PROTONS but different numbers of neutrons

in the shell the electrons represent

electron binding energies

what are the first few letters of the electron orbital shells

K
L
M
N

the total number of electrons in the orbital shells is equal to

the number of PROTONS

ionized

an atom that had an extra electron or one removed

an ionized atom

is not neutral, the charge equals magnitude to the difference between the electrons and protons

atoms cant be ionized by the

addition or subtraction of protons because they are bound very strongly

what happens in the interaction between an xray and a carbon atom

x ray transfers energy to an electron and ejects the electron from the atom and an ion pair is formed

in most atoms the number of neutrons is

always GREATER than the number of protons

the lighter the atom

the greater the abundance of neutrons over protons

maximum electrons per shell formula

2n²

the shell number n stands for

principal quantum number

the most important quantum number of the 4 quantum numbers is

principal quantum number

the number of electrons in the outermost shell is equal to

group on the periodic table

the number of the outermost electron shell is

equal to its period in the period in the periodic table

the outer shell is always limited to ____ electrons

8

what happens in the 4th period

electrons are added to an inner shell

transisitional elements