December 1, 2014- Welcome Back!

Homework: Read pgs. 26-28 DoNow: Update T.O.C Pg. 41- Chemical Equations pg. 42- Conservation Mass/Chemical Equations -Open textbook to pg. 25- Look at Figure 9 On pg. 41 Identify the elements and the number of atoms for each element in the chemical formulas listed in figure 9 (Skip water and Carbon dioxide)

What is in a Chemical formula? A combination of symbols that represents the elements in a compound.

Ex: NaCl CO2 Subscripts represent….? - the number of atoms of an element in a molecule or the ratio of elements in a compound.

What’s in a Chemical Equation?

Think about what goes into a recipe? What's a recipe you know?Ingredients are the reactants- mixed/combined together and once they are combined (chemical reaction) they produce (yield) something new, a product.Reactants- the materials you have at the beginning of the equationProducts- the different materials you have at the end of the equation, after the reaction.

Create your own Recipe of Reactants & Products

For the list of Chemical Equations make a “recipe” card that includes:

-The written equation, label the reactant side and product side -List the elements or formula(s) on the reactant side of the equation, and the number of atoms for each

EX: Reactants: H2 + 02 - 2 Hydrogen atoms, 2 Oxygen atoms -Repeat for the product side of the equation -Be creative in your description

December 2, 2014 Homework: Answer Figure 11- Problem Solving question (on pg. 27) Section 2 Review (pg. 31) problems 1,2 all on binder pg. 42 Do Now: Agenda- Write H.W. Open textbook to pg. 26- Look at Figure 10- Read the caption and observe the diagram- Answer the question on pg. 42 of your binder:How do you know that mass has been conserved in the reaction?

How Do We Know Mass Was Conserved?

The mass of the reactants (14 grams + 8 grams) equals the mass of the products (22 grams).

How can we define the Law of Conservation of Mass in terms of Reactants and Products?

The mass before the reaction = the mass after the reaction. (Reactants) (Products)

Model Conservation of Mass Lego Lab Activity: Build a model that demonstrates that the Law of Conservation of Mass is true in chemical equations.

Challenge equation -Ask for additional Lego's Build a model and follow the same procedure for the equation below:

Fe2O3 + C Fe + CO2

What are your results? Why do you think you received these results? What do you think you can do to the equation so it follows the Conservation of mass?

Conclusions… What were your results?

Assess Yourself! Write the # on your paper

Which statement BEST describes you after this activity?1) I’m a Novice: -I’m just starting to learn this, and I really don’t understand it yet2) I’m an apprentice: -I’m starting to get it , but I still need someone to coach me through it.3) I’m a Practitioner: - I can mostly do it by myself, but I sometimes mess up or get stuck.4) I’m an Expert: I understand it well, and I could thoroughly teach it to someone else.

One sentence summary… In a one sentence summary answer : How do the numbers of the atoms (and mass) for the reactants of a chemical equation compare with the atoms (and mass) for the products?

December 3, 2014 Homework: Finish Class work: Copy the sample problem from pg. 29 and complete practice problems 1 & 2. (Due Tomorrow) Do Now: Agenda- Write homework---Take out last nights homework (pg. 42)Update T.O.C- pg. 43: Coefficients/Balancing Chemical EquationsTake out an expo marker (if you have one)Open textbooks to pg. 27-

Homework Review Fig. 11: Before the fire: measure the masses of oxygen and wood (reactants) After: measure the masses of the ashes and escaped gases after (products).Section 2: questions 1 & 2:

Identifying a balanced equation…

Sharpen your Skills Activity Complete Sharpen your Skills Activity from pg. 28 of your textbook on pg. 43 of your binder

Then you may begin copying sample problem from pg. 29 onto binder pg. 43 (EXACTLY HOW IT IS WRITTEN)