This time we are going to find unsatrured hydrocarbon, means they are not single bond.
Alkene= double bonded
Alkyne=triple bonded
Naming is simialr to the alkane, you just need to put -ene instead of -ane. Same as alkyne -ene instead of -ane.
Ex,2-hexene
first you write down the number of carbon which is 6
c c c c c c
the 2 represent where double bond is
c-c=c-c-c-c
then put hydrogen
CH3-CH=CH-CH2-CH2-CH3
Notice where second carbon and third carbon only have one hydrogen.
Alkyne= Triple bond
This is very similar to the double bond
ex, 3-Hexyne
Same as alkene, the number represent where the bond is, and it's triple, thus there is no hydrogen in third and fourth( between fourth and fifth sould be - sorry)
Hydro Carbon- Molecule that only consist with hydrogen(H) and Carbon(C).
Since, Carbon has 4 valence electrons, it can bond to four sides.
Ex, Methane. Like you see Carbon goes middle because it is futher away from the full shell than hydrogen and Hydorgen bonds on four side.
This is called Alkane, it is satured hydrocarbon(single bond)
There are three ways to show Alkane
what you see in example is full structure.
other one is called condensed structure. It looks like this.
ex, methane
CH3CH2CH3
and last one is called molecular formula
ex,methane
C3H8
Number of carbon determine the name of alkane and also number of hydrogen.
Name you just need to memorize, but number of hydrogen is easy. You just need to multiple number of carbon and add 2. Ex) Methane CH4, 1x2=2 2+2=4 4 hydrogen
Note: not always hydrogen bonds to carbon, it can bon with other carbon
Alkyl group is an alkane which has one missing hydrogen,and it attaches to alkane group(branched hrdro carbon)
Ex, CH3-Methyl=CH3 attached to propane.
When you named it is, 2-methly-Propane. the number only indicate which carbon it attached to, you can read from left to right or right to left.
Bonding involves valence electrons only.
Atoms gain, lose, or share electrons until they have a stable octet. There are 3 types of Bonding.
1) Ionic Bonds. An Ionic bond is formed when 2 electrons are transferred amongst each other.
2) Nonpolar Covalent bonds. A Nonpolar Covalent bond is formed when electrons are shared equally.
3) Polar Covalent Bonds. A Polar Covalent bond is formed when electrons are shared unequally.
Electrostatic Force
An electrostatic force exists between charged particles because of attraction or repulsion. Operates equally with each direction getting equal amounts of energy. Charged particles are put into crystal latices.
Basic Electrostatic Relationships:
1) Opposite charges attract each other.
2) Similar charges reject each other.
3) The longer the distance apart from 2 charged particles, the smaller the attracting force is between them.
4) The stronger the force of attraction is dependent on the charge of the particle.
Ionic Bonds
Metals usually lose valence electrons to non-metals, while non-metals gain the non-metals. This is an example of electrons being transferred. Once metals lose electrons they become positively charged ions or Cations. Once non-metals gain electrons they become negatively-charged ions or Anions. They are very strong with high melting points, its take massive amounts of energy to break them apart.
Electronegativity
The value of the tendency of an atom to take away electrons from near by atoms. Metals tend to have low electronegativity values in comparison Non-metals have higher values. The scale that is applied to measure electronegativity is the Pauling Scale. This scales goes from Os & Fr which is 0.7 on the scale to 4.0 which is Fluorine. Atoms with high values of Electronegativity will actively attract their own electrons and electrons from near by atoms. Ionization Energy also part takes in this.
Calculating Electronegativity Difference
The simple formula is below. In caps.
ENEGRY DIFFERENCE= {ENERGY 1 - ENERGY 2}
Non Polar Covalent Bonding
Covalent bonds like Ionic bonds are strong and need large amounts of energy to break them apart.Non polar covalent bonding has equal amounts of energy spread apart. It is constructed when two atoms don't have completed shells. They share one or more electron trying to satisfy the Octet rule. The electrons at the same time are attracted to the nucleus of each atom. Non-metals will not let go of their own electrons. Single molecules that contain intramolecular covalent bonds are attached together with intermolecular forces.
Polar Covalent Bonding
Molecules that have electronegativity differences between .5-1.8 are thought to be covalent. But without equal sharing of electrons. This is called a Polar Covalent bond. An atom with a greater electronegativity will pull the electron toward its self and the electron will be closer to the atom with a higher electronegativity.
Electrons are represented by dots in electron dot diagrams. The nucleus is represented by the atomic symbol. There are 4 orbitals having at most 2 electrons per orbital. Each orbital is given an electron before it pairs up. The dots are put into 4 groups.With 8 electrons signifying a closed shell or noble gas.
Lewis Diagrams:
1) Firstly you must find out how many valence electrons are in your chosen elements. Adjust this number by subtracting an electron for each positive charge. Or by adding an electron for a each negative charge in the atom. Then count the electrons remaining.
** You want your atom to become stable, the only way to do this is by having 8 electrons in the outer shell. (Hydrogen only needs 2 electrons)
2) Then select your central atom. A central atom is the atom that is the farthest away from a closed shell. (Metal Ion goes in center if available) H&F are an exception.Place the electrons so they fill each orbital.
3) Use the remaining valence electrons to fill out the orbitals. Place remaining electrons on the central atom.
4) Make multiple bonds if the central atom is not an octet.
Covalent Compounds
Two atoms share a pair of electrons to create a full outer shell. This pair is called the Bonding Pair.
Lone pairs or non-bonding pairs are the pair of electrons which do not join together. Single bonds can be represented by 2 dots or a single line.
-people believed everything was made up of fire, earth, wind, and water.
However, a russian chemist Dimitri Mendeleev would be the first person to write a periodic table. He grouped different elements based on their properties.
Periodic Trends
Metallic Properties: The properties of the elements change fro metallic to non-metallic going left to right across the periodic table.
The elements become more metallic going down a family in the periodic table.
Atomic Radius
Atomic radii of an atom increases going across a row left to right, it also increases going down a group.
Going left to right across a given period the atomic number (and number of protons) increases, and the positive charge on the nucleus increases.
Ionization Energy: is the energy need to completely remove an electron from an atom. Ionization energy increases going up and to the right. All noble gases have high ionized energy. Helium has the highest ionization energy while Francium has the lowest.
Electronegativity: Is the tendency of an atom to attract electrons from a neighboring atom. Electronegativity energy increases going across a row left to right. It decreases going down a group.
Reactivity: When a metal moves down a row and right it becomes more reactive. Non-metals are the opposite as once they go up a row they become more reactive.
Melting & Boiling Point: Elements from the centre have a higher boiling point and Noble Gases have
