Blog Post 2

Blog Post 2 (Unit 2)

source: wallpapers-and-backgrounds website: http://wallpapers-and-backgrounds.net/science-wallpaper

1. Draw or describe a particle diagram of an element and compound

Description:  

An element - An element, is a collective substance made up entirely of one type of atom. There are more than 100 different elements, that are the composition of all physical things (that possess a mass) on earth. They are joined by chemical bonds, creating often more complicated forms. 

A compound - A compound, is a collective substance made up of more than one different type of atom. Also referred as a mixture (either homogeneous or heterogeneous). There is a definite ratio of the different atoms, and they are joined by chemical bonds, forming molecules that cannot be separated by physical means. 

1. Draw or describe a homogeneous and heterogeneous mixture.

Description: 

A homogeneous mixture is a blend of multiple different components, that can be combined in a way that the overall mixture has a uniform composition in all respects. 

A heterogeneous mixture is a blend of multiple different components that cannot be combined in a way that the jumble is uniform throughout, and there are obvious separations between the components.  

1. Make a list of 5 physical and 5 chemical properties

Physical: 

• Color
• Volume
• Freezing point
• Temperature
• Mass 

Chemical: 

• toxicity 
• Flammability 
• types of chemical bonds formed 
• The heat of combustion 
• chemical stability 

1. Make a list of 5 physical and 5 chemical changes.

Physical:

• Melting ice cube.
• Chopping wood.
• dissolving another substance into the water. 
• The sublimation of dry ice. 
• Mixing water and oil. 

Chemical:

• Mixing an Acid and a Base.
• Baking a cake.
• Cooking an egg.
• Burning a piece of wood.
• Rusting iron.

1. Describe the 4 states of matter and how energy affects its composition.

Solid - The addition of energy to a solid, causes its componential atoms/particles to move. This, in turn, triggers the solid to switch phases into a liquid due to the increased movement and energy.

Liquid - When more energy is added to a liquid, the particles and atoms increase the speed of their movement until they become airborne and can then be considered a gas.

Gas - Even more energy is added, the gas begins to

Plasma 

1. Describe the 8 different phase changes between the different states of matter.

1. Freezing - The removal of heat from a substance which results in a change from liquid to solid.

2. Melting - The addition of heat to a substance which results in a change from solid to liquid. 

3. Sublimation  - The evaporation, or direct transformation of a substance from solid to gaseous. 

4. Evaporation - The heating of a liquid to the point that it transforms into a gaseous state. 

5. Dissolving - The homogenous combination of two substances, typically solid and liquid to liquid only. 

6. Smoke  - The burning of a solid object until it becomes particularized and gaseous throughout the air. 

7. Condensation - The phase change from gaseous to liquid by the addition of colder temperatures. 

8. Freeze-drying - The freezing, the sublimation of ice particles, so that the substance itself is intact. 

1. Create a pie graph of the %composition of each of the chemicals in the separation of mixture lab. (Either sand, salt, and iron  or  silicon dioxide, sodium chloride, and ammonium chloride).

1. Describe the physical properties used to separate the three chemicals in the lab.

Sublimation, one of the defining properties of the ammonium chloride, was used to initially remove it and measure its absence. The mixture was heated over a hotplate beneath a fume hood, and its gaseous state was evaporated away. Next, water was added to the mixture. This caused the sodium chloride to dissolve into the water, and therefore be evaporated out after being filtered through a coffee filter. Leaving only the silicon dioxide behind.