1. Today’s Do Now 1. Balance the following chemical equation: ___C 2 H 6 + ___O 2  ___CO 2 + ___H 2 O 2. How does balancing chemical equations relate to the law of conservation of mass?

2. Formula Review Write the formulas for the following names: 1. Magnesium hydroxide 2. Iron (III) sulfide 3. Dinitrogen Hexoxide Mg(OH) 2 Fe 2 S 3 N2O6N2O6

3. Writing and Balancing Chemical Equations

4. By the end of class, we will be able to… Write balanced chemical equations when provided with a written description

5. Today’s Game Plan Do Now 10 minutes Writing a balanced equation 15 minutes Balancing Equations Lab 60 minutes Exit Ticket 5 minutes

6. In order to write chemical equations you need: 1. Correct formulas 2. State of matter 3. Number of moles of each reactant/product (balanced equation)

7. Diatomic Molecule: a molecule containing two atoms

8. Elements that Exist as Diatomic Molecules ElementFormula HydrogenH2H2 NitrogenN2N2 OxygenO2O2 FluorineF2F2 ChlorineCl 2 BromineBr 2 IodineI2I2 This only applies when an element is by itself

9. Steps to Writing Balanced Equations: 1.Read the description of the reaction. Underline the reactants, products and their states. Solid chromium(III) oxide, nitrogen gas, and water vapor can be combined together to form solid ammonium dichromate.

10. Steps to Writing Balanced Equations: 2. Write the unbalanced equation that includes the underlined information. Solid chromium(III) oxide, nitrogen gas, and water vapor can be combined together to form solid ammonium dichromate. ___Cr 2 O 3 (s) + ___N 2 (g) + ___H 2 O(g)  ___(NH 4 ) 2 Cr 2 O 7 (s)

11. Steps to Writing Balanced Equations: 3. Balance the equation starting with the most complicated molecule ___Cr 2 O 3 (s) + ___N 2 (g) + 4 H 2 O(g)  ___(NH 4 ) 2 Cr 2 O 7 (s)

12. Today’s Game Plan Do Now 10 minutes Writing a balanced equation 15 minutes Balancing Equations Lab 60 minutes Exit Ticket 5 minutes

13. Today’s Game Plan Do Now 10 minutes Writing a balanced equation 15 minutes Balancing Equations Lab 60 minutes Exit Ticket 5 minutes

14. Exit Ticket 1. Sodium bromide reacts with chlorine gas to produce sodium chloride and bromine. 2. Aluminum reacts with hydrochloric acid (HCl) to yield aluminum chloride and hydrogen. 3. Aluminum metal and oxygen gas combine to produce aluminum oxide (Al 2 O 3 ). Which of these is the balanced equation for this reaction? a) Al + O 2  Al 2 O 3 b) 2Al + 2O 2  2Al 2 O 3 c) 2Al + 3O 2  5Al 2 O 3 d) 4Al + 3O 2  2Al 2 O 3

15. Today’s Homework Writing and Balancing Chemical Equations worksheet