Unit 3 A.7-A.9

Intermolecular forces are a force of attraction and repulsion between molecules. In the fractioning tower, molecules in the bottoms with more carbon atoms do not vaporize. Ball-and-stick models is a molecular model where each ball represents an atoms and each stick represents a pair of shared electrons connecting two atoms. Another molecular model is called a space-filling model which shows atoms in contact with each other. Alkanes are a hydrocarbon containing only a single covalent bond. When assembling a 3-D model of a methane molecule, the 3-D shape is called a tetrahedron, a regular triangular pyramid where the four bonds of each carbon atom in an alkane point to the corners of a tetrahedron. A molecular formula is a chemical expression indicating the number of each atom type within a molecule. Condensed formulas are more useful than molecular formulas and they are a chemical formula that provides additional information about bonding.

Unit 3 Sec. A Summary HW 3

7/15/14

17) a. C₉H₂₀

b. C₁₀H₂₂

c. C₁₆H₃₄

d. C₁₈H₃₈

18) a. 128g

b. 142g

c. 226g

d. 254g

19) a. Propane C₃H₈

b. Pentane C₅H₁₂

20) Yes because all three molecules have the same number of elements and subscripts.

21)

 

22) Ethane

23) Molecules can be represented as both a linear chain or as a zigzag chain because the elements and subscripts are the same but just in a different pattern.

Unit 3 A.4-A.6

A carbon footprint is the quantity of greenhouse gases emitted based upon individual activities measured in kilograms of carbon dioxide. Distillation is a process that separates liquid substances based on differences in their boiling point. If you heat a liquid mixture containing two components, the component that would vaporize first would be the component with the lower boiling point. To separate crude oil you must apply distillation techniques to large-scale oil refining. The refining process producing several distinctive mixtures is called fractions. Fractional distillation is a process of separating a mixture into its components by boiling and condensing the components. In a distilling column the temperature is the highest at the bottom and the lowest on the top. In distillation the vaporized molecules moves up in the distilling column. Bottoms are components from petroleum found in the lower trays of a fractionating tower after distillation.

Unit 3 Sec. A Summary HW 2

7/14/14

9) Fractional distillation separates mixtures into its components by boiling and condensing the components.

10) Acetone and water because the different boiling points allow it to easily separate.  

11)

12)

13) Simple distillation separates the liquid substances based on differences in their boiling point while fractional distillation separates a mixture into its components by boiling and condensing the components.

14) Light petroleum: gasoline

Intermediate: diesel

Heavy distillates and residue: wax

15) Bottom of the distillation tower because components of petroleum are found there.

16) By increasing the boiling point of the chemical components, it would separate the compounds.

Petroleum

Petroleum is a liquid. Crude oil is unrefined liquid petroleum that has been pumped from underground. Refined petroleum contains a mixture of various hydrocarbons, which is a molecular compound containing only atoms of the elements hydrogen and carbon. Petroleum is mostly used as a fuel and about 89% of all petroleum is burned as fuel. Its other major use is as a raw material manufacturing CDs, sports equipment, clothing, automobile parts, plastic charge cards, etc. Petroleum is a nonrenewable resource because the hydrocarbon fuel is used up and takes millions of years to replace it.

Unit 3 Sec. A Summary HW

7/12/14

1) A hydrocarbon is a molecular compound composed only of carbon and hydrogen atoms.

2) To refine a natural resource is the removal of impurities from a desired material.

3) Petroleum is used as a fuel and raw materials like CDs, sports equipment, and automobile parts making it a valuable resource. 

4) Approximately 66% of the world’s known crude oil reserves are found in the Middle East.

5) Crude means a material that is not yet processed.

6) a. 0.11 x 20,000,000 = 2,200,000 barrels

b. 0.89 x 20,000,000 = 17,800,000 barrels of petroleum

7) Mineral oil, asphalt, kerosene, paraffin wax, motor oil, and household lubricating oil.

8) a. CDs, clothing, plastic charge cards, and automobile parts.

b. CDs could be made of metal, clothing could be made of cotton, plastic charge cards can be made of paper, and automobile parts can be made of copper.

Unit 1 Sec. D Summary HW 4

7/10/14

13) Steel

14) An example of a well-defined compound is Ni₃Al, which is a low-density, strong metallic alloy of nickel and aluminum.

15) Sustainability is present-day activities that preserve the ability of future generations to meet their resource needs.

16) a. Reusing is using the same product again and recycling is when an item is gathered for reprocessing.

b. Reusing examples: wearing clothes more than once and reusing a textbook

    Recycling example: recycling water bottles and recycling paper

17) a. Renewable resources examples: lumber, corn, solar energy, and wind power

b. Nonrenewable resources examples: fossil fuel, gas, nuclear, and oil

18) a. Reusing

b. Recycling

c. Reusing

19) A light bulb is glass so it must get melting to form a new product and newspapers must get shredded so it can be forming into a new product.

20) A scientific law is a statement that is always true and a law enacted by a government can be broken.