Homework # 3

2SAS #26-34

26. Metallic elements are likely to loose electrons because they form cations.

27. Since the noble gas family of elements rarely looses or gains electrons, this shows that they are both unreactive and chemically inert.

28. a. Na: cation
      b. Ca: cation
      c. F: anion
      d. Cu: cation
      e. O: anion
      f. Li: cation
      g. Sn: cation
      h. I: anion

29. Copper metal and copper (II) ions are more chemically similar. This is because copper is a reactive metal that will form ions. Oxygen with a mass of 16 and oxygen with a mass of 18 are not chemically similar because there is a clear difference in the number of protons and neutrons which makes them dissimilar.

30.
      156 + 254 = 410
      410/2= 205 pm

31. a. change in color
         - chemical: rusting
         - physical: painting
      b. change in temperature
         - chemical: combustion
         -physical: freezing or boiling a substance
      c. formation of a gas
          -chemical: reaction with HCl and Cu
          - physical: water will become a gas when it it boiled

32.
    a. Bromine (Br)
    b. Silicon (Si)

33. Mendeleev organized the periodic table by using both atomic weight and the similarities in chemical and physical properties of the elements. In the Snake River data, we also had to analyze properties of dissolved substances and compare their mass to see what could have dissolved in a specific type of water.

34. In the periodic table, two examples that mock Mendeleev's way of organizing the original table by atomic weight would be to put argon ( atomic weight 39.95) after potassium (atomic weigh 39.10), and put cobalt (atomic weight 58. 93) after nickel ( atomic weight 58.96).


2SBS #1-8

1. Two resources typically found in each of the three major "spheres" of Earth:
     -Atmosphere: nitrogen, oxygen, neon, and argon
     -Hydrosphere: water and some dissolved minerals
     -Lithosphere: petroleum and metal-bearing ores

2. a. Three major parts of lithosphere:
       - Crust is hard soil and rock with much of earth's minerals
       - Mantle is the middle of the lithosphere
       - Core is the center of earth that is very hot
    b. The crust serves as the main storehouse of chemical resources used in manufacturing consumer products for various companies.

3. a. Silver: Mexico
    b. Copper: Japan
    c. Tin: China

4. Out of the United States, Australia, China, and Brazil, it seems that China produces the largest quantities of the resources from the table.

5. Minerals are found in ores. Minerals differ from ores because minerals are solid compounds containing the element of interest in a group, while ores are naturally formed rocks or minerals that can be mined or used to extract a metals and other minerals. 

6. The factors that determine the feasibility of mining a particular metallic ore at a certain cite include...
- the quality of the ore found at the site
- the percent of metal in the ore
-the type of mining and processing needed to extract the metal form its ore
-the distance between the mine and metal
- the metal's supply-versus-demand status 
- the environmental impact of the mining and metal processing

7. I think the factors that could have influenced the decision to reopen the gold mine that was inactive for over 100 years may be because there was a higher demand for gold, or more gold was found in a surrounding region and people wanted to check if there was some in that mine.

8. Quantitiy of useful ore:   the amount, usually as a percent, of the desired mineral being mined at the site