Atomic Structure, Atomic Number, Atomic Weight, and Isotopes

what does and atom consist of

a central nucleus

what does a central nucleus contain

protons, neutrons, and electrons in orbit around shells in the nuclues

protons have a _______ charge, and are ______ in size to neutrons

positive, equal

neutrons are ______

uncharged

Electrons are much _______ than protons and neutrons, and have a ______

smaller, negative

what does an electrically neutral atom have

an equal number of protons and electrons

what are ions

atoms that gain or lose one or more electrons and become charged

how do you find out the atomic number of an element

the number of protons in atoms of an element

how do you find out the atomic weight

number of protons + the number of neutrons

what are isotopes

when atoms have the same atomic number but a different atomic weight

some isotopes are ______

stable

unstable isotopes are_______ and give off ________

radioactive, radiation

how do atoms for chemical bonds

by attaching to each other by gaining, losing, or sharing electrons

where are electrons found

in shells around the nucleus

what are shells 

areas of space

the first shell is closest to the nucleus. How many many electrons can it hold

2

The second and third energy shells hold a maximum of how many electrons

8

Atoms of elements that have their outermost shells filled are…..

stable and chemically inert