CHEMISTRY SHENANIGANS

In today's class, we learned about homogeneous and heterogeneous substances, as well as solutions, pure substances, and how to tell the difference, and mixtures and how to separate them.

• Homogeneous substances consist of only one visible component (i.e. distilled water, oxygen) 
• Heterogeneous substances contain more than one visible component (i.e. chocolate chip cookie) We also learned about what pure substances are. There are two type of pure substances, elements and compounds.
  
• There are two types of pure substances:
1. Elements: substances that cannot be broken down into simpler substances by chemical reactions (i.e. oxygen, iron, magnesium)
2. Compounds: substances that are made up of two or more elements and can be changed into elements or other compounds by chemical reactions (i.e. water, sugar)
• How to tell the difference between an element and compound:
1. The differences are really only visible on an atomic level
2. Electrolysis: to connect the substance to an electric current, and split the compound apart into its constituent elements
   
• Solution: a homogenous mixture of two or more substances that may not always involve liquids (i.e. fog, steel)
1. Solvent: the component present in a solution that is in greater amount
• water is the most common solvent
• the symbol (aq) is used when something is dissolved in water
2. Solute: the component present in a solution that is in lesser amount
   
• Mixtures: many are easy to identify, but others are easily confused as pure substances
  
1. In heterogeneous mixtures, the different parts are clearly visible (i.e. granite, sand, fog)
2. In homogenous mixtures, the different parts are not visible (i.e. salt water, air, brass)
3. Separating mixtures is a physical change. There are many methods to separate mixtures, depending on the type of mixture:
• by hand, filtration -> are for heterogenous mixtures only
• distillation, crystallization, chromatography

MATTER

What is Matter?
-Anything that has mass and occupies space

-Matter can exist in many different states, the most common are:
a)solid,liquid,gas
b)plasma, aqueous,amorphous
Solids: Holds one shape and has a definite volume (has strong bonds)
Liquid: Can change shape, but has a definite volume (has weak bonds)
Gas: Can change shape and volume (has no bonds)




CHANGES IN MASS
-Matter can undergo many changes
-Nearly all changes can be broken down into three catagories:
-Physical Changes
-Chemical Changes
-Nuclear Changes



Physical Change
-Involves changing shape or state of matter (Crushing, Tearing, etc.)
-No new substances are formed (Boiling water, Cutting wood, Smashing cars)

Phase Changes
-Changing from a solid to a gas can often be confused as a chemical change
-Chemcials remain the same
-During the melting process chemicals usually follow this path

Chemical Change
-New substances are formed
-Properties of the matter change
-Conductivity
-Acidity, colour etc.
-ex. Iron rusting, burning wood, digesting food

Conservation of Matter
-In physical and chemical changes, matter is neither created nor destroyed. Ever! PERIOD!
- This is called the Conservation of Matter



Thus ends the lesson of the class..

Today, we did our Unit 1 Test in class. For homework, we had to read a bit about the periodic table as a preview for the lesson.

In today's class, the labs were finished up by all groups. It was also the last class before the Unit 1 Test, so we were reminded of what to study and know for next class. This would include WHMIS symbols, safety in the laboratory, scientific notation, dimensional analysis, unit conversions, SI units and metric prefixes, inaccuracies in measurement, as well as graphing.

Below are some useful pieces to know and help study for the upcoming test:



A tidbit on scientific notation..




Some examples on conversions and dimensional analysis..





For useful study tools in SI units and metric prefixes, visit the past post titled Measurement & Chemistry. Good Luck!

Last class, we did our first lab.

Just a reminder of what NOT to do in the lab..


Problem: What is the maximum amount of Sodium Chloride you can dissolve in 200mL of
water?



We completed 4 trials one with 10mL, another with 20mL, one with 30mL and the last one with 40mL. After figuring out the maximum mass of salt we can dissolve in each amount of liquid, we graphed the points. From there we then tried to estimate the maximum amount of Sodium Chloride we can dissolve in 200mL of water from a line of best fit.

Our results:

Trial	Volume of Water (mL)	Mass of Salt (g)
1	10	0.70
2	20	1.83
3	30	2.67
4	40	3.62

Today in class, we learned about unit conversions. We also learned about scientific notation and looked through the equipment in our class. In addition, we did an experiment with a balloon blowing out fire when it gets heated with some elements. Just like converting currencies in Chemistry, it is usually necessary to convert between units. This process is called Dimensional Analysis and is demonstrated below.

Today in class, we were taught the importance of measurements in Chemistry, as well as a bit of background information on the common systems of measurement. While the Metric system was founded about 30 years ago in France, the most common system we use today is the SI system. In addition, we discovered the 7 fundamental units of Chemistry as well as several prefixes and SI units.

7 FUNDAMENTAL UNITS:


PREFIXES & SI UNITS: