VBALLCHIICA

Q. What part of an atom is affected in a chemical reaction? A. The outermost shell of atom is effected in a chemical reaction. Prentice Hall Biology (book) Q. What is happening during a chemical reaction? A. Chemical reactions are changes involving breaking and forming of chemical bonds or transformations of elementary particles.

Fe (nail)+O2= rust A chemical reaction happens when 1+ chemicals form into others. i.e. iron+oxygen= rust gurl= _cH96PSJ7jA0/RwmANKAWWxI/AAA AAAAAAFo/feMqmtv81qg/s400/ BACHarbin_061202_1454_3.JPG&img refurl= 2007/10/make-mine-rusty- nail.html&usg=__M6Eq8I4pbfp_BbDY qYAxMoLXAWQ= &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 Common_Round_Iron_Nail.summ.jpg

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)

 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

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)

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)

 Exothermic: - Reactions that gives off heat - i.e. table salt Na(s) + 0.5Cl 2 (s) = NaCl(s)  Endothermic: -Reactions that absorb heat/energy - i.e. photosynthesis - sunlight + 6CO 2 (g) + H 2 O(l) = C 6 H 12 O 6 (aq) + 6O 2 (g) 50&q=define%3A+endothermic+reaction

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

Combustion Synthesis Combustion is when the substances in a compound are mixed with O 2 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 C x H y + O 2 --> CO 2 + H 2 O

Decomposition Single Replacement 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 Types of Chemical Reactions

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

 KI + Pb(NO 3 ) 2