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SCIENCE STUDENTS
GROUP SEVEN
SCIENATICS
LECTURE 1:
*ELECTRONEGATIVITY
-the higher the value the higher the attrction of electron in other elements
*IONIZATION ENERGY
-the higher the value ,the easier to attract an electron
-the lower the value,the easier to remove an electron
LECTURE 2:
*OCTET RULE
-it tells that elements gain or lose or phase electrons to achieve the electronic configuration of the nearest noble gas
*VALENCE ELECTRON
-electrons that are located in he outermost shelf
*IONIC BONS
-it is the complete transfer of valence electron(s) between atoms.
*IONS
-it is the atom that has gained or lost one or more electrons and therefore has a positivity charge or negatively charge
*IONS
-atom that has lost a valence electron and has a postive charge
*ANIONS
-atom that has gained a valence electron and has a negatively charge
*COVALENT BOND
-created when pair of electrons are shared by atoms
*POLAR BOND
-created when pair of electrons between atoms that are not equally shared
*NON-POLAR BOND
-created when atoms are sharing their electrons equally
LECTURE 3:
*PAULIS EXCLAUSION PRINCIPLE
-an orbital may hold a maximum of tw electron ; these electron must be opposite
*AUFBAU PRINCIPLE
-starts in low
*HUNDS RULE
-in filling up the same orbital ; parallel spin before filling
LECTURE 4:
*METALLIC BONDING
- "SEA OF ELECTRON"
* PROPERTIES OF METAL
1. MALLEABILITY
-can be hammerd of flattered in shape
EX. Au (Gold) Ag(Silver)
2.DUCTILITY
-can be drawn into wire
EX. Cu (Copper)
3.CONDUCTILITY
-good conductors of heat and electricity
4.TENSILE STRENGHT
5.SONOROUS
-sound of metal
6.CLUSTER
-shining metal
7.MELTING POINT
BOILING POINT
8.ALL METALS ARE SOLID AT THE ROOM TEMP. EXCEPT
-Hg (Mercury) -Cs (Cesium)
-Ga (Gallium) -Fr (Francium)
-Br (Boron)
LECTURE 5:
*CARBON
-the versatile atom
*CARBON VERSATILE
-can form single,double and triple bonds with another carbon
-can form chains,branched chains and rings
*CATENATION
-linkage of atoms of the same element into longer chains responsible for the existence of a large number of organic compounds
-----> ORGANIC COMPOUNDS <-----
-Glucose -Protein
-Fats -Vitamins
-Amino Acids -Minerals
*ALLOTROPES
-different forms of a chemical element
*ALLOTROPES OF CARBON
1. DIAMOND
-the hardest mineral
-formed by extreme pressure and temperture
-high melting point
-stable network of covalent bond and hexagonal rings
-->USES OF DIAMONDS
->cutting,drilling,grinding
->Jewelry
->semi-conductor industry
2. GRAPHITE
-most stable form of carbon
-used in thermochemistry as a standard state for defining the heat
-good conductor
-vast electron delocalization within the carbon leaves
-->USES OF GRAPHITE
->Pencil Lead
-> Lubricant
->Fire Retardants
->Brake Linings
3. BUCKMINSTERFULLERENE
-buckyball
-20 hexagons & 12 pentagons
-Harold Kroto,Robert Curl, Richard Smaleey -1996 Nobel Prize Chemistry
4. GRAPHINE
-single layer of carbon
LECTURE 6:
*ORGANIC COMPOUNDS
-compounds composed of carbon atoms with Hydrogen, Oxygen,Sulfur, and Nitrogen
-naturally produced by living organisms
*FRIEDRICH WOHLER
- 1828 synthesized urea from ammonium cyanate
-shatterd the vitalism theory
*PROPERTIES OF COMMON ORGANIC COMPOUNDS
1. VISCOSITY
-a measure of fluids resistance to flow
2. LUBRICANTING OIL
-used luricant parts of machines and protect metals from rusting.
3. VOLATILITY
-measure of the tendency of substance to evaportae or turn into gaseous state.
- EX. Acetone
Ethanol alcohol
4. FLAMMABILITY
-measure of how material easily burns
- EX. Kerosene
Gas
LECTURE 7:
*HYDROCARBONS
ALKANES
-Methane (Gas) -Butane (Gas) -Heptane (Liquid)
-Ethane (Gas) -Pentane (Liquid) -Octane (Liquid)
-Propane (Gas) -Hexane (Liquid)
ALKENES
-Ethene (Gas) - 1-Pentene (Gas)
-Propene (Gas) - 1-Hexene (Liquid)
- 1-Butene ( Gas)
ALKYNES
-Ethyne (Gas) -Pentyne (Liquid)
-Propyne (Gas)
- 2-Butyne (Gas)
LECTURE 8:
*MOLE
-counting unit in chemistry
----> 1 mole of any substance = Avogadro's number (6.02 x 10 (raised to 23 particles)
*AMADEO AVOGADRO
- n=mole(mol)
PROBLEM SOLVING
1. How many moles of carbon dioxide is formed when 0.529 mol of C3H8 is burned?
GRESA
GIVEN: 0.539 mole C3H8
REQUIRED : moles of CO2
EQUATION : 1 mole of C3H8 = 3 mole CO2
SOLUTION : mole CO2 = 0.529 mol C3H8 x 3 CO2
ANSWER :1,587 moles of carbon dioxide
1
mol C3H8
LECTURE 9 :
* ATOMIC MASS
- is the weighted avereage of the masses of each of the isotopes of an element.
*MASS NUMBER
- is the sum of the number of protons and neutron in the nucleus of an atom.
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