intro to atoms
DESCRIPTION
Intro to Atoms. Atoms : the basic particle in which all elements are made Nucleus : The central core of an atom containing protons and neutrons In the nucleus are: Proton : small, positively charged particle in the nucleus of an atom ( + symbol) - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/1.jpg)
Intro to AtomsAtoms: the basic particle in which all elements are
madeNucleus: The central core of an atom containing
protons and neutronsIn the nucleus are:
• Proton: small, positively charged particle in the nucleus of an atom ( + symbol)
• Neutron: Neutral charged particle in the nucleus of an atom
Outside the Nucleus:• Electron: tiny, negatively charged particle that moves
around the nucleus of an atom
![Page 2: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/2.jpg)
Laws of Science
Law of Conservation of Matter• Matter cannot be created or destroyed
Law of Conservation of MassEstablished by French Chemist Antoine Lavoisier• In a chemical reaction, the mass of the
products equals the mass of the reactants. THIS IS EXTREMELY IMPORTANT WHEN
BALANCING EQUATIONS
![Page 3: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/3.jpg)
What’s the MATTER?Matter: anything that has mass and takes up
space.Mass: measurement of how much matter is in
an objectElement: a substance that cannot be broken
down into any other substances by chemical or physical means
Compound: a substance of 2 or more elementsMixture: 2 or more substances that are mixed
together, but NOT chemically combined
![Page 4: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/4.jpg)
Atomic ModelsEarly Models/Theories of the Atom:
Dalton’s Atomic Model:- All matter is composed of atoms- Atoms cannot be made or destroyed- All atoms of the same element are identical- Different elements have different types of atoms
- Atoms of 2 or more elements can join together to form a compound
![Page 5: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/5.jpg)
Modern Atomic Model – NOT ON YOUR PAPER!
• Electrons form a negatively charged cloud around the nucleus
• Cannot determine the location of an electron at any given time
![Page 6: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/6.jpg)
Atomic Models continued…JJ Thomson’s Model:
• Atom is positively charged• Discovered Electrons
Rutherford’s Model:• Protons and the nucleus• Electrons orbit around the positively charged nucleus
Chadwick’s Model:• Discovered neutrons
Bohr’s Model:• Electrons move in specific layers (shells)• Electrons move when atoms absorb or give off energy, moving
from one shell to another
![Page 7: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/7.jpg)
Atoms and ElementsAtomic number • number of protons in an element • Number of electrons the element hasAtomic mass: mass of one atom of the elementHow to calculate neutrons: atomic mass # - atomic
numberValence electrons: electrons that can be transferred from
one atom to another or may be shared between atomsChemical symbol: symbol for element (H – Hydrogen) (C
– Carbon)
![Page 8: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/8.jpg)
Periodic TableDmitri Mendeleev
• Created first Periodic Table• Arranged elements in order of increasing
atomic mass• Placed similar elements in the same group
according to their reactionsPeriods: a horizontal row in the P.T. Groups: vertical columns in the P.T. – also known
as families due to similar characteristics
![Page 9: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/9.jpg)
![Page 10: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/10.jpg)
Groupings
• Metals (Alkali , Alkali Earth)• Nonmetals• Nobel Gases• Transition Elements• Halogens• Common Elements
![Page 11: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/11.jpg)
Valence Shells
Group 1 = 1 valence electronGroup 2 = 2 valence electronsGroup 13 = 3 valence electronsGroup 14 = 4 valence electronsGroup 15 = 5 valence electronsGroup 16 = 6 valence electronsGroup 17 = 7 valence electronsGroup 18 = 8 valence electrons (full shell)
![Page 12: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/12.jpg)
Properties of Metals
• Classified by its physical properties such as shininess, malleability, ductility, and conductivity.
Malleable: can be hammered flat or into other shapes
Ductile: can be pulled out into a long wireConductivity: ability to transfer heat from one
object to another
![Page 13: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/13.jpg)
Metals continued…Chemical properties: ability of a pure substance to
change into another substance.Reactivity: The speed in which an element combines
or reacts with other elementsCorrosion: the wearing away of metal due to a
chemical reaction
Metals can be considered an alloy which is a mixture of a metal with one other element (usually found together in nature)
![Page 14: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/14.jpg)
Physical and Chemical Properties
Physical• Def: a change that does not
result in the formation of any new substances
• Examples: Dissolving sugar in waterMelting ice cubesBoiling waterCrumbling Paper
Chemical• Def: a change that
produces one or more new substances
• A chemical reaction will take place
• Burning paper• Corrosion • Rusting• Milk or eggs going BAD
![Page 15: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/15.jpg)
Nonmetals
• Lack the properties of metals• Poor conductors of electricity and heat• Reactive with other elements• Dull and brittle (break easily)• Good insulators
![Page 16: Intro to Atoms](https://reader035.vdocument.in/reader035/viewer/2022062815/56816939550346895de0a432/html5/thumbnails/16.jpg)
Metalloids & Noble Gases
Metalloids• Metalloids has
characteristics of both metals and nonmetals
• Semiconductors: substances that can conduct electricity under some conditions
Noble Gases• Unreactive elements• Exist in Earth’s atmosphere