Lab 2C : Chemical and Physical change

What we are doing today is shown from below step:

1)Wear safety goggles and lab apron
2)Otain 1/3 solution in each four test tubes
3)Place a clean medicine dropper in each test tubes and set it in the test tube rack
4)Draw a grid as it shown in the lab book (P.19) on our note
5)There will have six different combination on each cell of grid
6)Record and make comments in your tube
7)Clean up
8)Wash your hands thoroughly with soap and water

Chemical change:
-New substances are prodused
-irreversible . Ex. burning anything, cooking

Physical change:
-No new substance is formed
-chemical composition does not change
-reversible Ex. Melting point, boiling point

Through these conditions from above between Chemical and Physical change, we can determind what kind of change does the matter is happening by those conditions.

~mATTER~

WHAT IS MATTER?????

Matter is the Stuff Around You

Matter is everything around you. Matter is anything made of atoms and molecules. Matter is anything that has a mass.

                                 Matter can be divided into :

   Pure substance                        &                       Mixture

    

       can be divided into :                            can be divided into :

Element   &    Compound                    Homogeneous  &    Hetergeneous                             

                                                                                                  

(Element is made of atoms)                           (Homogeneous uniform throughout)

(Compound is made of elements)                  (Hetergeneous isnt uniform)

Element can be divided into :                  

Metal, metaloid and non-metal

Compound can be divided into :

Ionic and covalent

Elements and compounds can move from one physical state to another and not change = physical change

For example : Oxygen (O₂) as a gas still has the same properties as liquid oxygen. The liquid state is colder and denser but the molecules are still the same.

If the formula of water were to change, that would be a chemical change = chemical change

For example : If you added another oxygen atom, you would make hydrogen peroxide (H₂O₂). Its molecules would not be water anymore.

More properties of matter :

Matter is commonly said to have 3 states

1. SOLID------rigid

 Don't change shape easily experiences small changes in volume when heated.

2. LIQUID

Takes the shape of the container and experiences slight changes in volume when heated.

          

 3 . GAS

Takes the shape of the container and experiences dratic

 in volume when heated

Class 2

So basically this class we learnt about the unit conversion chart and some unitary rates, We thought this class was kind of annoying because at first because its actually pretty confusing while you got to memorize all these units while we already needed to prepare a quiz for this. But thats kind of what we did in this class.

Chemistry 11 note: Scientific Notation Sept 21, 2010

Scientific Notation- is used to express very large or very small number using powers of 10
Ex1

Express in scientific form:
a) 25 000 000 000

Ex2Express in standard form ( basicly it's the opposite way)

Generally, when the power of 10 is positive, the point will move to the right side; otherwise(which is negitive) it moves to the left side.