Bonding, Chemical Reactions study guide

 

 

 

Bonding, Chemical Reactions study guide

 

The following texts are the property of their respective authors and we thank them for giving us the opportunity to share for free to students, teachers and users of the Web their texts will used only for illustrative educational and scientific purposes only.

 

All the information in our site are given for nonprofit educational purposes

The information of medicine and health contained in the site are of a general nature and purpose which is purely informative and for this reason may not replace in any case, the council of a doctor or a qualified entity legally to the profession.

 

 

Bonding, Chemical Reactions study guide

Bonding, Chemical Reactions and a review of stuff you keep forgetting

Characteristics of Chemical Reactions

  • Formation of a NEW substance, not the original substance
  • Reactant:  substance that enters into the reaction (original substance)
  • Product: substance that is produced by a chemical reaction (new substance)
  • The Law of Conservation of Mass states that mass remains constant in a chemical reaction

Endothermic Reactions

  • “endo” means into, and “thermic” means heat
  • Heat, or energy, goes into an endothermic reaction
  • The reaction absorbed is usually in the form of heat or light also
  • Endothermic reactions are COLD feeling

                      4 letters each: ENDO and COLD

Exothermic

  • “Exo” means out of and “thermic” means heat
  • Heat, or energy, comes out of, or is released, in an exothermic reaction
  • Any reaction that involves combustion or burning is exothermic
  • Exothermic reactions are HOT feeling

                      3 letters each:  EXO and HOT

Vocabulary

  • Exothermic: Heat, or energy, comes out of, or is released (gets hot), combustion
  • Endothermic: Heat, or energy, goes into (gets cold), reaction is the form of heat or light
  • Collision Theory:  The rate of a reaction is affected by concentration, surface area, temperature and catalysts

Chemical Bonding

  • Chemical bonding – the combining of atoms of elements to form new substances.
  • The rules of chemical bonding are determined by the structure of the atom.  The outermost energy level determines if it will bond or not.
  • Valence electrons – the electrons in the outermost energy level of an atom.

Bonding

  • If an atom has 8 valence electrons it is stable and will not bond
  • An atom with less than 8 valence electrons is unstable and will bond readily (easily)
  • The ability to bond determines its ability to undergo chemical reactions

           Number of valence:             What happens:
1, 2, 3                                  lose electrons
5,6,7                                              gain electrons
4                                                    gain or lose
8                                                    unresponsive

  • Ionic bonding – involves a transfer of electrons.  One atom gains and the other one loses (metal and non-metal)
  • Covalent bonding –They share electrons, rather than transfer.  (Non-metal and non-metal), form molecules
  • Metallic bonding:  metal and metal, electrons are able to fly off the energy levels

 

Ionic Bonding

  • Ionic bonding – involves a transfer of electrons.  One atom gains and the other one loses.
  • Ion – a charged atom (positive or negative). 
  • Example:  Fluorine (F) has 7 valence electrons and to become stable, it gains 1 electron to fill its outermost level and becomes a negative ion.
  • Remember all atoms want 8 valence electrons

METALS AND NON METALS BOND

Covalent bonding

  • Covalent bonding – occurs between atoms that have high ionization energy (a lot of valence electrons) and high electron affinity (attracts electrons). 
  • They share electrons, rather than transfer.  “Co” means to share.
  • Simplest example:  Hydrogen

                                       H : H

  • Covalent bonds form molecules.
  • A molecule is the smallest  particle of a covalently bonded substance that                       shares all the properties of that substance.

NONMETAL AND NONMETAL

Metallic Bonding

  • Metallic bonding – bond when the positive nuclei are surrounded by mobile electrons.  (all attracted at the same time).  This allows the metals to be heat conductors. 
  • Referred to as the “sea of electrons”
  • This is when the electrons are able to come off of their electron orbits and move freely.

METALS AND METALS

More Vocabulary

  • Chemical bonding – the combining of atoms of elements to form new substances
  • Ion – a charged atom (positive or negative).
  • Ionization – the process of removing electrons to form ions. 
  • The energy needed to remove the electrons is called  ionization energy.
  • Electron affinity – the tendency of an atom to attract electrons.
  • Polyatomic ion – when two elements bond first covalently then through ionic bonding
  • Oxidation number – the number of electrons an atom gains or loses, or shares in a chemical bond.
  • Diatomic elements – form bonds with atoms of the same element.

Balancing Equations

  • Subscripts, symbols, and formulas cannot be changed because you would be changing the substance altogether.
  • Coefficients can be added.
  • Balance the number of atoms of each element on both sides to show that no mass has been lost or gained
  • Practice at home: http://www.wfu.edu/~ylwong/balanceeq/balanceq.html

Periodic Table

  • Dmitri Mendeleev Organized by atomic mass (weight)
  • Henry Moseley, arranged the elements according to their atomic number.  We use his model.

Groups / Families

  • Groups or families, same thing different names
  • They have similar properties
  • Vertical
  • They have the same number of valence electrons
  • There are 18 families… be able to name them!!
  • A,AE,T,B,C,N,O,H,NG

Families to know

  • Alkali Metal Family:  most reactive metals, violent reaction in water
  • Halogen Family:  most reactive nonmetals
  • Noble Gas Family: normally unreactive

Periods/ Rows

  • Elements are not alike in the rows
  • First element in a row is an extremely active solid, last is always an inactive gas
  • There are 7 periods
  • The number of the row they are in tells you the number of energy levels
  • Horizontal

Element stuff you need to know

  • Hydrogen is a non-metal
  • Hydrogen and Helium are the lightest elements
  • Mercury is the only metal in liquid form at room temperature
  • Most of the elements are metals in solid form
  • The non-metals are in gas form
  • There are only a few metalloids along the zig-zag line
  • Radioactive elements are mostly man-made

 

Source : http://pams-zajac.wikispaces.com/file/view/unit+7+Bonding+and+Reaction+Notes.doc

Web site link to visit: http://pams-zajac.wikispaces.com

Google key word : Bonding, Chemical Reactions study guide file type : doc

Author : not indicated on the source document of the above text

If you are the author of the text above and you not agree to share your knowledge for teaching, research, scholarship (for fair use as indicated in the United States copyrigh low) please send us an e-mail and we will remove your text quickly.

 

Bonding, Chemical Reactions study guide

 

If you want to quickly find the pages about a particular topic as Bonding, Chemical Reactions study guide use the following search engine:

 

 

Bonding, Chemical Reactions study guide

 

Please visit our home page

 

Larapedia.com Terms of service and privacy page

 

 

 

Bonding, Chemical Reactions study guide