1. Chemical Reactions Chapter 13

2. Objectives  SPI 0807.9.3 Classify common substances as elements or compounds based on their symbols or formulas.  SPI 0807.9.8 Interpret the results of an investigation to determine whether a physical or chemical change has occurred.  I can: 1. Identify the signs of a chemical reaction. 2. Identify a compound by its chemical formula. 3. Write a formula for a covalent compound. 4. Name a covalent compound given its chemical formula.

3. Chemical Reaction  Process in which one or more substances change to make one or more new substances  Signs of a chemical reaction  Gas formation (gas bubbles)  Color change  Precipitate forms (a solid produced)  Energy given off (light, thermal, electrical, heat)  Formation of new substance  Breaking of bonds  Making new bonds I can identify the signs of a chemical reaction.

4. Gas Formation Nitrogen dioxide Energy Change Light heat Precipitate forming Silver chromate Color Change I can identify the signs of a chemical reaction.

5. Chemical Formula  A shorthand way to use chemical symbols and numbers to represent a substance  Examples:  H 2 O  NaCl  CO 2  CaF 2  C 6 H 12 O 6 I can identify a compound by its chemical formula.

6. Formulas for Covalent Compounds  Uses prefixes that tells how many atoms of each element are in a formula  Change the ending of the last atom to -ide Mono-1 Di-2 Tri-3 Tetra-4 Penta-5 Hexa-6 Hepta-7 Octa-8 Nona-9 Deca-10 I can write the formula of a covalent compound.

7. Write the formulas for each compound 1. Antimony tribromide 2. Hexaboron silicide 3. Chlorine dioxide 4. Hydrogen iodide 5. Iodine pentafluoride 6. Dinitrogen trioxide 7. Diboron hexahydride 8. Diphosphorus pentoxide I can write the formula of a covalent compound.

8. Name these covalent compounds 1. P 4 S 5 2. SeF 6 3. Si 2 Br­ 6 4. SCl 4 5. CO 2 6. B 2 Si 7. NF 3 I can name a covalent compound given its chemical formula.

9. Objectives  SPI 0807.9.3 Classify common substances as elements or compounds based on their symbols or formulas.  SPI 0807.9.8 Interpret the results of an investigation to determine whether a physical or chemical change has occurred.  I can: 1. Name a ionic compound given its chemical formula.

10. Formulas for Ionic Compounds  Change the negative ion’s ending to –ide  Examples:  NaCl  Sodium chloride  MgCl 2  Magnesium chloride  CaF 2  Calcium fluoride  Li 2 O  Lithium oxide I can name an ionic compound given its chemical formula.

11. Objectives  SPI 0807.9.10 Identify the reactants and products of a chemical reaction.  SPI 0807.9.11 Recognize that in a chemical reaction the mass of the reactants is equal to the mass of the products (Law of Conservation of Mass).  I can: 1. Identify the products and reactants of a chemical reaction. 2. Identify the number of atoms for each element in a molecule. 3. Define the Law of Conservation of Mass. 4. Balance an equation using the Law of Conservation of Mass.

12. Chemical Equations  Represents a chemical reaction that uses symbols and formulas  Reactants – starting material in chemical reaction (before arrow)  Products – substances formed from chemical reaction (after arrow)  Coefficient – number placed in front of a chemical symbol or formula I can identify the products and reactants of a chemical equation.

13. Determine the number of atoms for each element. 1. NaCl 2. H 2 O 3. 3NaCl 4. 12H 2 O 5. 4C 6 H 12 O 6 6. (PO 4 ) 2 7. 6(NH 3 ) 3 I can determine the number of atoms for each element in a molecule.

14. Balancing Equations  Law of Conservation of Mass – mass cannot be created or destroyed in ordinary chemical and physical changes  Atoms of reactants = atoms of products  Atoms are never lost or gained, just rearranged I can define the Law of Conservation of Mass.

15. Balancing Equations 1. Count the atoms of each element 2. Balance uneven atoms, by placing coefficients in front of symbol or formula 3. Place coefficients as needed until all atoms are balanced 4. Double check your work I can balance a chemical equation using the Law of Conservation of Mass.

16. Objectives  SPI 0807.9.8 Interpret the results of an investigation to determine whether a physical or chemical change has occurred.  SPI 0807.9.10 Identify the reactants and products of a chemical reaction.  SPI 0807.9.11 Recognize that in a chemical reaction the mass of the reactants is equal to the mass of the products (Law of Conservation of Mass).  I can: 1. Identify the six types of reactions: Synthesis, decomposition, single-displacement, double- displacement, combustion, acid-base.

17. Types of Reactions 1. Synthesis Reaction – rxn in which 2 or more substances combine to form one new compound.  A + B → AB  Examples:  2 NH 3 + H 2 SO 4  (NH 4 ) 2 SO 4  2 H 2 + O 2  2 H 2 O I can identify the six types of reactions.

18. Types of Reactions 2. Decomposition Reaction – rxn in which a single compound breaks down to from 2 or more simpler substances.  AB → A +B  Examples:  NH 4 OH  NH 3 + H 2 O  2 KClO 3  2 KCl + 3 O 2 I can identify the six types of reactions.

19. Types of Reactions 3. Single-Displacement Reaction – rxn in which one element takes the place of another element  A +BC → AB + C  Examples:  3 Pb + 2 H 3 PO 4  3 H 2 + 1 Pb 3 (PO 4 ) 2  H 2 + 2 NaOH  2 Na + 2 H 2 O I can identify the six types of reactions.

20. Types of Reactions 4. Double-Displacement Reaction – rxn in which ions from two compounds exchange places.  AB + CD → AC + DB  Examples:  1 Li 3 N + 3 NH 4 NO 3  3 LiNO 3 + 1 (NH 4 ) 3 N  2 AlBr 3 + 3 K 2 SO 4  6 KBr + 1 Al 2 (SO 4 ) 3  2 NaBr + 1 CaF 2  2 NaF + 1 CaBr 2 I can identify the six types of reactions.

21. Types of Reactions 5. Combustion – produces CO 2 and H 2 O  Examples:  4 C 5 H 9 O + 27 O 2  20 CO 2 + 18 H 2 O  2 C 8 H 18 + 25 O 2  16 CO 2 + 18 H 2 O  1 C 3 H 8 + 5 O 2  3 CO 2 + 4 H 2 O 6. Acid-Base Reaction – acid reacts with base producing water and a salt  Examples:  3 HBr + 1 Al(OH) 3  3 H­ 2 O + 1 AlBr 3  HCl + NaOH  H 2 O + NaCl I can identify the six types of reactions.