chem2._Atoms_Molecules_and_Ions.pptx - ATOMS, MOLECULES AND...

This preview shows page 1 - 11 out of 44 pages.

ATOMS,MOLECULESAND IONSLesson 2
ATTENDANCEf95cQK4f7
PriestlyIt was Democritus who first proposed the idea of atom.In late 1700, chemists Started to explain chemical behavior in terms of atoms.JosephPriestlyandAntoine Lavoisier, established the period for foundation of chemistry bydemonstrating that the substances combine to form new substance.Lavoisier
In 1785 he formulated the thelaw ofconservation of masswhich state that“in any closed systemtransfer of matterand energy, the mass of the systemremains constant”PriestlyLavoisier
Finally, in 1803, an English chemist,JohnDalton,proposed and developed thaatomic theory.
Dalton'sAtomicTheoryAll matter consists of tiny principle calledatom.Atoms cannot be destroyed nor created.Elements are characterized by the weight oftheir atoms.In any chemical reactions, atoms combine insmall, whole number ratios.When elements react, their atoms maycombine in more than one -whole numberratio.Definite proportions
Atomic StructureMarble model -John DaltonPlum pudding model– J.J. ThomsonNuclear model (Gold-FoilExperiment)- Ernest RutherfordPlanetary Model- Neils BohrQuantum Mechanical Model- ErwinSchrodinger
Subatomic Particles(Proton, Electronsand neutron)
Subatomic Particles(Proton,Electrons and neutron)The particles that are smaller than the atom are calledsubatomic particles.The three subatomic particles that form an atom areproton, electron, and neutron.the central part of theatomis callednucleus.
Subatomic Particles(Proton, Electronsand neutron)WhereZis themass numberequal to the sum ofprotons and neutrons in the nucleus atomAis theatomic numner

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 44 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Fall
Professor
NoProfessor
Tags
Chemistry, Atom, Electron, Ion, Sodium chloride

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture