1. BELL WORK 1/21/16 ANSWER ALL 3 OF THE FOLLOWING QUESTIONS: IS NaCl AN ELEMENT OR COMPOUND? EXPLAIN WHAT SKILL YOU NEED TO KNOW TO SOLVE THIS? DOES A CHEMICAL REACTION OCCUR TO FORM NaCl?

2. AGENDA 1.BELL WORK 2.REVIEW CHEMICAL REACTIONS 3.INTRO CHEMICAL FORMULAS & BALANCING EQUATIONS 4.GROUPWORK (1-3-6 PROTOCOL) 5.INDEPENDENT PRACTICE 6.EXIT TICKET (PLICKERS)

3. STUDENT LEARNING OBJECTIVES SPI 0807.9.2 IDENTIFY THE COMMON OUTCOME OF ALL CHEMICAL CHANGES SPI 0807.9.3 CLASSIFY COMMON SUBSATNCES AS ELEMNTS 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 CHANGES 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) TOC: #62 CHEMICAL REACTIONS NOTES

4. ESSENTIAL QUESTIONS: 1. CAN I IDENTIFY THE REACTANTS AND PRODUCTS OF A CHEMICAL EQUATION? 2. CAN I EXPLAIN THE LAW OF CONSERVATION OF MASS?

5. WHAT IS A CHEMICAL REACTION? A CHEMICAL REACTION IS THE PROCESS OF A SUBSTANCE COMPLETELY CHANGING TO A DIFFERENT SUBSTANCE WITH DIFFERENT PROPERTIES WHY ARE THERE CHEMICAL REACTIONS? CHEMICAL REACTIONS HAPPEN WHEN MOLECULES BUMP INTO EACH OTHER CAUSING THE STARTING BONDS TO BREAK APART, THE ATOMS REARRANGE, AND NEW BONDS ARE FORMED

6. CH 4 + O 2 → CO 2 + H 2 O EXAMPLE: CH 4 + O 2 → CO 2 + H 2 O Yield sign means EQUAL to SAME CARBON Methane fire

7. 7 CLUES OF A CHEMICAL REACTION: 1.CHANGE IN COLOR 2.FORMATION OF GAS 3.SOLID FORMED CALLED PRECIPITATE 4.LIGHT IS EMITTED 5.CHANGE IN TEMPERATURE 6.CHANGE IN SMELL OR TASTE 7.IRREVERSIBLE

8. CHEMICAL SYMBOL - SHORTER WAY TO WRITE AN ELEMENTS NAME. CHEMICAL FORMULA -SHORTHAND WAY TO USE CHEMICAL SYMBOLS AND NUMBERS TO REPERESNT A SUBSTANCE.

9. A CHEMICAL FORMULA SHOWS THE NUMBER OF ATOMS OF EACH ELEMENT IN A MOLECULE EXAMPLES: H 2 O SO 4 Ca(OH) 2

10. CHEMICAL FORMULAS USE SUBSCRIPTS AND COEFFICIENTS TO SHOW THE NUMBER OF ATOMS AND MOLECULES. SUBSCRIPTS THE SMALL NUMBER TO THE RIGHT OF THE ELEMENT THAT TELLS THE NUMBER OF ATOMS Examples: H 2 O SO 4 Ca(OH) 2

11. COEFFICIENTS - LARGE NUMBER TO THE LEFT OF THE ELEMENT. APPLIES TO TO THE WHOLE MOLECULE! 2H 2 O H = ____ O=_____ *Look at the molecule below. How many Hydrogen atoms are in the molecule? How many Oxygen atoms?

13. GROUP WORK (OF 3): THINK, PAIR, SHARE 3Ca(OH) 2 Ca = ____ O = ____ H = ____ 4SO 4 S = ____ O = ____

14. CHEMICAL EQUATION CHEMICAL EQUATION IS AN EASIER AND SHORTER WAY TO WRITE A CHEMICAL REACTION USING CHEMICAL SYMBOLS AND FORMULAS AS A SHORTCUT TO DESCRIBE A CHEMICAL REACTION LAW OF CONSERVATION OF MASS LAW OF CONSERVATION OF MASS STATES THAT MASS CAN NOT BE CREATED OR DESTROYED

15. EXAMPLE: CH 4 + O 2 → CO 2 + H 2 O Reactants: what you start with Products: what you end with An equation is balanced when the number of atoms in the reactants are = to the number of atoms in the products

16. 4H2O4H2O4H2O4H2O H2OH2OH2OH2O 2H2O2H2O2H2O2H2O You balance an equation by changing the coefficients, not the subscript!

17. *MOVE AROUND THE ROOM TRUE OR FALSE Coefficients are used as multipliers against the Subscripts to balance chemical equations.

19. __ Fe + __S → __FeS Element BeforeAfter Fe = ____ _____ S = ____ _____ Example #1

20. __H 2 + __O 2 → __H 2 O ELEMENT BEFOREAFTER H = ____ _____ O = ____ _____ Example #2

21. __Mg + __O 2 → __MgO Element BeforeAfter Mg = ____ _____ O = ____ _____ Example #3

24. EXIT TICKET When balancing equations, you can NEVER change the... a. Coefficient b. Subscript c. Whole number d. Atom

25. EXIT TICKET When balancing equations, you can NEVER change the... a. Coefficient b. Subscript c. Whole number d. Atom