Slide 1:Structure of the Atom


How are atoms studied? :How are atoms studied? Atoms are the building blocks of matter Atoms are too small in size to study easily Size of Earth : soda can = soda can : atom


Who studied the atom? :Who studied the atom? Studied by many scientists for centuries Democritus (400 BC) – phrase “atomos” Rutherford (1911) – nucleus (gold foil expt) Moseley (1913) – X-rays to find atomic # *Bohr (1913) – planetary model of the atom *Schrödinger (1923) – electron cloud model


Slide 4:The Bohr Model


Slide 5:e I’m an electron! I’m a proton! I’m a neutron! P N


Slide 6:e I was walking along and I saw these two. I was telling jokes to the neutron. The proton and I were having fun.


Slide 7:e They looked so happy there together. I was p o s i t i v e l y charged! I couldn’t have amassed more happiness. P N P N P N P N e e e


Slide 8:e The proton looked happy, so I wandered closer. I could see the electron coming near. The who? Huh? e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e


Slide 9:They were HUGE next to me! The electron was so cute! Like a speck of dust, or something… e


Slide 10:I didn’t want to seem obvious, so I kept walking. Around and around the electron goes. Hey electron, you’re making the proton dizzy. e e e e e e e e e e e e e e e e e e e e e e e e


Slide 11:The proton seems so happy with the neutron. I’m having fun, but I still notice the electron. It won’t bother me if the electron hangs around. e


Slide 12:I guess I’ll just wander around out here. I’m happy hanging out here. The center is cool, but sometimes it can be a “Bohr”. e e e e e e e e e e e e e e e e e e e e


Slide 13:Electrons circle around the nucleus of an atom. Protons are a main part of the nucleus of an atom. Neutrons also hang out in the nucleus of an atom. e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e


Slide 14:Electrons have a negative charge. ? Protons have a positive charge. + Neutrons have no charge. 0 e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e


Slide 15:Electrons are little and have a mass of almost zero. Protons are big and have a mass of one. Neutrons are also big and have a mass of one. e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e


Slide 16:e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e The Bohr Model


What is the structure of an atom? :What is the structure of an atom? Nucleus – center of the atom Home of Protons and Neutrons Proton Has a positive (+) charge Has a relative mass of 1 Determines the atomic number Found inside the nucleus P


What is the structure of an atom? :What is the structure of an atom? Neutron Has no (0) charge Has a relative mass of 1 Determines the isotope Isotopes are two of the same element with different masses Found inside the nucleus N


What is the structure of an atom? :What is the structure of an atom? Electron Has a negative (-) charge Has a relative mass of 0 (zero) Determines the ion Found outside the nucleus Bohr model – electrons are in specific energy levels Electron cloud model – electrons are in a random cloud e


What is the structure of an atom? :What is the structure of an atom? Bohr Model “Planetary Model” Schrödinger Model “Electron Cloud Model”


How are P, N, e- related? :How are P, N, e- related? # protons = atomic number # electrons = # protons in a neutral atom # protons + # neutrons = atomic mass


Slide 23:What is a chemical symbol? Chemical symbol tells us what atom it is Always a CAPITAL LETTER, sometimes followed by a lower case letter Ex: Oxygen O Nitrogen N Sodium Na *Cobalt – Co *Carbon Monoxide – CO (Co is an element, CO is a compound)