Chemical Changes (Reactions) Reactants Products Synthesis Single Replacement Double Replacement Decomposition

Chemical Reactions Indicators – Fizzing (gas produced) – Color change – Gets cloudy/precipitant (solid produced) – Heat released or absorbed – Light emitted – Odor changes

Chemical Reactions Reactants  Products H 2 O 2  H 2 O + O 2 – What are the reactants? What are the products?

Chemical Reactions There are 4 kinds of Chemical Reactions that occur: Synthesis Decomposition Single Double Replacement Replacement

Chemical Reactions Synthesis – Two or more reactants are combined to form one product. +

Chemical Reactions Decomposition – One reactant breaks down into two or more products. +

Chemical Reactions Single Replacement – An element and a compound combine. – One element from the reactants replaces another in the products. ++

Chemical Reactions Double replacement – Two compounds combine. – Two elements in the reactants switch places in the products. ++

Chemical Reactions-Practice Identifying Example #1 H 2 + O 2  H 2 O Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Example #2 Li 3 P  Li + P Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Example #3 Na + MgCl 2  Mg + NaCl Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Example #4 SiCl 4 + O 2  SiO + Cl 2 Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Example #5 C 5 O 3  C + O 2 Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Example #6 Rb 2 O + AlF 3  RbF + Al 2 O 3 Which is it? Synthesis Decomposition Single Replacement Double Replacement

Chemical Reactions Law of conservation of Matter – Atoms are not created or destroyed – The number of atoms at the START of a reaction, there must be the same number of atoms AFTER the reaction. – Equations must be balanced!

Chemical Reactions Balancing Chemical Equations STEPS: – Count the number of atoms for each element in the reactants and in the products. – Compare the numbers to see if each element is balanced (equal) with itself. – Use WHOLE NUMBER coefficients to “fix” unbalanced elements. Do not change the subscripts!

Chemical Reactions Example #1 H 2 + O 2  H 2 O

Chemical Reactions Example #2 Li 3 P  Li + P

Chemical Reactions Example #3 Na + MgCl 2  Mg + NaCl

Chemical Reactions Example #4 SiCl 4 + O 2  SiO + Cl 2

Chemical Reactions Example #5 C 5 O 3  C + O 2

Chemical Reactions Example #6 Rb 2 O + AlF 3  RbF + Al 2 O 3

Chemical Reactions Example #7 SnO 2 + H 2 → Sn + H 2 O

Chemical Reactions Example #8 Mg(ClO 3 ) 2 + Na  NaClO 3 + Mg

Chemical Reactions Example #9 Al 2 (SO 4 ) 3 + RbF  AlF 3 + Rb 2 SO 4

Chemical Reactions Identify and Balance Al + F 2  AlF 3

Chemical Reactions Identify and Balance Ca(MnO 4 ) 2 + FeCl 4  CaCl 2 + Fe(MnO 4 ) 4

Chemical Reactions Identify and Balance Si 3 O  Si 8 + O 2

Chemical Reactions Identify and balance Cs 2 O + N 2  Cs 3 N + O 2

Warm Up Classify the following chemical reactions as decomposition, single replacement, double replacement or synthesis: For the first equation, what are the reactants and what are the products? Write the chemical formula for Barium Nitride

Acids and Bases

Acids & Bases Acids Examples: Citric Acids, Gastric Acid, Battery Acid, Sodas, tomatoes, etc. Properties: corrosive, produce H+ ions, sour taste, electrolytes, pH range = Examples of Formulas: HCl, H 2 SO 4, H 3 PO 4, HNO 3, etc

Acids & Bases Bases Examples: Soaps, Cleaning supplies, Hair Relaxers, etc. Properties: corrosive, produce OH - ions, bitter taste, electrolytes, slippery feel, ph range 7.1 to 14 Examples of Formulas: NaOH, KOH, Mg(OH) 2, Al 3 (OH), NH 3, NH 4 OH

Acids & Bases-pH Scale

Acids and Bases-Compare & Contrast

Acids and Bases--Identify 1.pH =2 2.HF 3.pH= 7 4.RbOH 5.Ca(OH) 2 6.pH= 9 7.Sour taste 8.Slippery feel 9.Electrolyte 10.pH = pH = 4 12.H 2 SO 4 13.HBr 14.FrOH 15.Corrosive 16.Bitter taste

Acids & Bases Neutralization Reactions Only an Acid can neutralize a base, and only a Base can neutralize an acid. H + comes off of the Acid and OH - comes off of the Base Acid + Base  Water + Salt HCl + KOH  H 2 O + KCl

Acid/Base Neutralization HBr + LiOH  _________ + _________ FrOH + HCl  _________ + _________ H 2 S + Mg(OH) 2  ________ + _______ ______ + HF  H KF ______ + CsOH  H CsI