Atomic structure

atom

smallest unit of an element that retains the properties of that element.

proton charge

positive

proton mass

1 amu (+)

what is inside the nucleus?

proton and neutron

neutron charge

neutral

neutron mass

1 amu (=)

electron charge

negative

mass of electron

no mass (≈ zero)

where is electron locacted

outside nucleus (electron cloud)

nucleus charge

positive

the nucleus is almost…

all the mass of the atom

electron cloud is where most of the…

volume is

atomic number

number of protons

what does the number of protons determine?

the element

atomic number

number of protons

Mass Number

sum of protons and neutrons

superscript of nuclear symbol

mass number

subscript of nuclear symbol

atomic number

Hyphen notation

the mass number is written with a hyphen after the element name

nuclear symbol

a type of shorthand notation that identifies the element (by symbol or atomic number) and the mass number of the element

7

Li

3

atomic number?

3

7

Li

3

mass number?

7

7

Li

3

number of protons?

3 protons

7

Li

3

number of neutrons?

4 neutrons

7

Li

3

number of electrons?

3 electrons

periodic table atomic number is a

whole number

average atomic mass has ______ on the periodic table

decimals

average atomic mass

79\.904 amu

mass number

80

atomic number

35

number of protons, neutrons, electrons (x, y, z)

35, 45, 35