i- the elements: a- substances that form all matter. 1- elements are pure substances that can not be...
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I- I- TheThe ElementsElements::
A- A- SubstancesSubstances thatthat formform allall mattermatter..
1-1- Elements are pure substances that can not be broken
down by heat, light, or electricity.
2-2- Elements contain only one type of atom. With the properties of that element.
3-3- Your body contains elements the most abundant being Oxygen, Hydrogen, Carbon, Calcium, Phosphorus, and Nitrogen.
B-B- DiscoveringDiscovering thethe ElementsElements:
1-1- Their are over 109 elements,
90 of them are found in nature.
2-2- In ancient times the people thought their were only 9 elements.
3-3- Marie & Pierre Curie discovered Radium and Polonium in 1898.
C-C- ChemicalChemical SymbolsSymbols
1-1- Is a shorthand form of the element’s name.
2-2- It always starts with a Capital letter. Helium’s =He,
Cobalt’s = Co, Oxygen = O.
3-3- Some elements come from their Latin names for exampleexample
gold = Au aurum lead = Pb plumbum
D- D- DescribingDescribing ElementsElements: : Scientist group elements according to their properties.
1-1- Most elements are metalsmetals or metallicmetallic elements.
a- LusterLuster = Shiny.
b-b- DuctileDuctile = can be drawn (mademade) into a wire.
c-c- MalleableMalleable = can be hammered, rolled, or shaped without breaking. (jewelry)d-d- Solid at room temperature.e-e- Conduct heat well.
2-2- NonmetalsNonmetals or nonmetallicnonmetallic have properties that are opposite of metals.
3-3- MetalloidsMetalloids have properties of metals and nonmetals. GermaniumGermanium, , ArsenicArsenic,, and SiliconSilicon used in computers.
II-II- PhysicalPhysical PropertiesProperties: make a substance identifiableidentifiable.
A-A- Examples =Examples = 1- taste 2- odor
3- hardness 4- color
5- density 6- magnetic 7- boiling & melting point
B-B- Physical ChangePhysical Change: is any change that does notnot alteralter {change} the chemical make-up of a substance.
1-1- Examples=Examples= Dissolving, evaporating, heating,
cooling, size, shape, or phase.
Ice melting Dissolving
EvaporatingFreezing
III-III- ChemicalChemical PropertiesProperties: Describes how two substances react with each other.
A-A-ProducingProducing ChemicalChemical ChangesChanges: Rust and tarnish are new materials with new properties both result from a
chemical change.
1-1- After a chemical change the properties of the original substance is no longer present.
Rust
Tarnish