Atoms and Sub Atomic Particles

Law of definite proportions

all samples of the same compound always contain the same proportions by mass of the component elements

electrons

negatively charged subatomic particles

protons

positively charged subatomic particles

neutrons

uncharged subatomic particles

proton properties

charge equal to +1.6022 × 10^-19 aka +1, mass is 1.6726 × 10^-24g aka about the same as a hydrogen atom

neutron properties

no charge, mass is 1.6749 x1 10^-24g

electron properties

charge is -1.6022 × 10^-19 aka -1, mass is 9.1094 × 10^-28g

atomic number(Z)

the number of protons in the nucleus of an element’s atom

mass number(A)

the number of protons and neutrons in the nucleus an element’s atom

neutron number(N)

the number of neutrons in the nucleus of an element’s atom

equation for mass number

A= Z + N

equation for neutron number

N= A- Z

isotope

an atom that contains a specific number of neutrons

isotope symbol

upper left is the mass number, bottom left is the atomic number