Test Review PowerPoint for 6th Period

Chemical Equations

Reactants are combined together to create products What are the reactants and products in the following equations? C + 2O CO 2 2H + O H 2 O Reactants and Products Reactants ReactantProductProducts What do you notice about these equations? Coefficients-big numbers (in front) Subscripts-small numbers (behind)

Label the reactants and products on the chemical equation below: CaCO 3 CaO + CO 2 Chemical Equations Reactants Products

Mg + O 2 MgO 2H 2 O 2 2 H 2 O + O 2 2Cu 2 O + C4Cu + CO 2 FeS + 2HClFeCl 2 + H 2 S P 4 O H 2 O4H 3 PO 4 Fe 2 O 3 + CFe + CO 2 SO 2 + O 2 SO 3 Label the reactants and products. On the practice worksheet.

Law of Conservation of Mass

You must end up with the same amount you started with. Mass cannot be created or destroyed Conservation of Mass

Matter is not created or destroyed

Balancing Chemical Equations

 Goal- Have the same number of atoms on both sides of the equation.  Rules ◦ Coefficients (numbers in front) multiply ◦ You can not change subscripts (numbers behind) ◦ If there is no subscript after an atom, then you know there is only 1 atom present Balancing Equations

1. Write equation 2. Count Atoms H O H O

Balancing Equations 3. Use coefficients to balance the equation H O

2 2 H O 4 2 4

H 2 + O 2  H 2 O H 2 + Cl 2  HCl SO 2 + O 2  SO 3 Mg + O 2  MgO Balancing Equations Practice

Reaction Rates

How do we make the reaction go faster? There are four things that we can change to make the reaction go faster. They are Temperature Surface area Concentration Using a catalyst

1. Temperature When we increase the temperature we give the particles energy This makes them move faster This means they collide with other particles more often So the reaction goes faster.

2. Surface area If we make the pieces of the reactants smaller we increase the number of particles on the surface which can react. This makes the reaction faster. The particles on the surface can react When cut into smaller pieces the particles on the inside can react

3. Concentration If we make one reactant more concentrated, there are more particles in the same volume to react So the reaction goes faster. There are less red particles in the same volume so there is less chance of a collision There are more red particles in the same volume so there is more chance of a collision so the reaction goes faster

4. Using a catalyst A catalyst is a chemical which is added to a reaction. It makes the reaction go faster. The catalyst does not get used up in the reaction. It gives the reaction the energy to get started

Enzyme catalyst

STATES OF MATTER video_id=274943

Simulation activity Gas matter that has no definite volume or shape. Molecules of a gas are so loosely arranged and move so rapidly that they will fill their container. Liquid matter that has definite volume but not shape. Since the molecules of a liquid are loosely packed and move with greater speed, a liquid can flow and spread. Solid matter that has definite volume and shape. The molecules are packed together tightly and move slowly.

Phase change is a physical property of matter Changing the amount of heat energy usually causes a temperature change. During a phase change energy is directed to making the phase change so the temperature does not change Do the following simulations with this link ate/index.html

_____________ the change from solid to liquid. _____________ the change from liquid to solid. ______________ the change from liquid to gas. ______________ vaporization from the surface of a liquid. ______________ vaporization from within as well as from the surface of a liquid. ________________ the change from gas to liquid. _________________ the change from solid to gas. _________________ the change from gas to solid. Melting Freezing Vaporization Evaporation Boiling Condensation Sublimation Deposition

Show computer graphic

Atoms Modern Atom Model Nucleus-Protons and Neutrons Electrons around nucleus, never know the true location

Protons Positively charged particle In nucleus Mass 1 amu

Neutrons Neutral (no) charge particle In nucleus Mass 1 amu

Electrons Negatively charged particle In electron cloud (orbitals) around the nucleus Mass 0 amu

Elements Made of atoms of one kind The type of element depends on the atomic number, or the number of protons it has Most elements occur naturally, but some have to be created in a lab

Periodic Table Elements are organized on the Periodic Table according to atomic number and properties of the element Open textbook to pages L14 – L15

Symbol The abbreviation letters used for each element

Atomic Number Number of protons (each element has a different # of protons) Number of electrons (same as # of protons so the element is electrically neutral)

Atomic Mass Mass of the Atom or # of the protons plus neutrons Each proton equals 1 amu and each neutron equals 1 amu (atomic mass unit) How do you find the average number of neutrons in an atom? atomic mass ( rounded) – atomic number

Groups Groups: or Family = columns Share similar properties Numbers on top indicate what group it is Noble gases-Group 18 (or 8A) Halogens-Group 17 (or 7A) Alkali metals-Group 1

Periods Periods = rows Atomic mass increases from left to right Number of protons increases from left to right Number of electrons in the outer shell of the atom increases from left to right Only hydrogen and helium are in the 1 st period

Look at L14 –15 or L186 – L187

A change in matter that results in one or more new substances. You change what it is. Chemical in the original substance combines with another chemical to create a new substance Chemical Changes

Evidence of Chemical Reactions or Change (2:52) Evidence of a Chemical Reactions

Evidence of Chemical Change New ________appears Bubbbles or ________ Precipitate forms (____ material) _____ is produced ______ is produced ______ is given off Difficult or impossible to __________ color fizzing solid reverse Heat Light Sound