170 likes | 437 Views
CHEMICAL REACTIONS. Maura Brown. Chemical Reaction Basics. Q. What part of an atom is affected in a chemical reaction? The outermost shell of atom is effected in a chemical reaction. Prentice Hall Biology (book). Q. What is happening during a chemical reaction?
E N D
CHEMICAL REACTIONS Maura Brown
Chemical Reaction Basics Q. What part of an atom is affected in a chemical reaction? • The outermost shell of atom is effected in a chemical reaction. Prentice Hall Biology (book) Q. What is happening during a chemical reaction? • Chemical reactions are changes involving breaking and forming of chemical bonds or transformations of elementary particles. http://en.wikipedia.org/wiki/Chemical_reaction
http://blogger.dotventures.com/Upload/ www.oxygennutritionalproducts.com/oxygen1.jpg http://img.alibaba.com/photo/100115508/ Common_Round_Iron_Nail.summ.jpg http://images.google.com/imgres?imgurl=http://bp1.blogger.com/ _cH96PSJ7jA0/RwmANKAWWxI/AAAAAAAAAFo/feMqmtv81qg/s400/ BACHarbin_061202_1454_3.JPG&imgrefurl=http://blog.beauharbin.com/ 2007/10/make-mine-rusty-nail.html&usg=__M6Eq8I4pbfp_BbDYqYAxMoLXAWQ= &h=400&w=266&sz=13&hl=en&start=8&um=1&tbnid=CgfYIdacDokLMM:&tbnh= 124&tbnw=82&prev=/images%3Fq%3Drusty%2Bnail%2Bpictures%26um%3D1%26hl%3Den Fe (nail)+O2= rust A chemical reaction happens when 1+ chemicals form into others. http://simple.wikipedia.org/wiki/Chemical_reaction i.e. iron+oxygen= rust
Reactants and Products • A reactant is the substance that is used in reactions. • A product is the new chemical made after the reaction took place. • i.e. (equation) Fe(reactant) + S(reactant) iron sulfide(product) http://www.nelsonthornes.com/secondary/science/scinet/scinet/reaction/change/reactant.htm
Law of Conservation of Mass • The Law of Conservation of Mass states that mass isn’t created nor destroyed in any ordinary chemical reaction. • Mass of substances/chemical reaction= mass of reactants http://www.mi.mun.ca/users/edurnfor/1100/atomic%20structure/tsld004.htm
Signs of a chemical reaction! • There are many ways to note if a chemical reaction has occurred. • i.e. precipitate ( solid made in a chemical reaction that is different from both of the reactants) • http://acpcommunity.acp.edu/Facultystaff/genchem/GC2/lab/chemrxn/signs.htm
Role of Energy Energy is the most vital factor in determining whether a reaction will or will not happen. Chemical reactions that discharge energy will occur suddenly. Chemical reactions that need energy won’t occur without an energy source. Prentice Hall Biology (book)
Types of Reactions • Endothermic: -Reactions that absorb heat/energy - i.e. photosynthesis • sunlight + 6CO2(g) + H2O(l) = C6H12O6(aq) + 6O2(g) http://www.google.com/search?hl=en&rlz=1T4GZHZ_enUS250US250&q=define%3A+endothermic+reaction • Exothermic: - Reactions that gives off heat - i.e. table salt Na(s) + 0.5Cl2(s) = NaCl(s) http://www.geocities.com/exothermicreactions/chemslide2.htm
Chemical Potential Energy • Chemical potential energy is type of potential energy that relates to the arrangement of molecules & atoms. • That arrangement could result in bonding of the chemicals http://en.wikipedia.org/wiki/Potential_energy#Chemical_potential_energy
Types of Chemical Reactions Combustion Synthesis http://library.thinkquest.org/2923/react.html CxHy + O2 --> CO2 + H2O Combustion is when the substances in a compound are mixed with O2 which then makes water and carbon dioxide. Combustion is a exothermic reaction i.e. Synthesis is when a combo of 2+ substances and a compound results. i.e. A + B --> AB
Types of Chemical Reactions Decomposition Single Replacement http://library.thinkquest.org/2923/react.html Decomposition is when a compound is made into simpler substances, usually by electrolysis When a single element replaces another, already-bonded element in a compound. i.e. A + BC --> B + AC http://www.marymount.k12.ny.us/marynet/stwbwk05/05flashchem/avreaction/avreaction.html
Types of Chemical Reactions: Double Replacement When elements in reactants combine again and make 2 different compounds Each product has one element from each of the reactants http://www.answers.com/topic/double-replacement-reaction-chemistry
Double Replacement Reaction • KI + Pb(NO3)2