Wednesday, July 10, 2013

2SAS (p.132) #26-28, 29-34 and 2SBS (p.151) #1-8

7/10/13

2SAS #26-34

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

27. Because noble gas elements rarely loose or gain electrons, this indicates they are 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 because since copper is a metal it will form ions because it is more reactive. While oxygen with a mass number 16 and oxygen with a mass number 18 are not chemically similar because there must have been a difference in the number of protons and neutrons making them not similar.

30. Estimate the diameter of a calcium ion (Ca2+): 205pm
      156 + 254 = 410
      410/2= 205 pm

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

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

33. Mendeleev used both atomic weight and the similarities in chemical and physical properties to organize the periodic table. 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 would need to be done to make it ordered by atomic weight like Mendeleev did 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.

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

4. Out of the United States, Australia, China, and Brazil; China produces the largest masses of the eight listed resources in the table

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

6. The factors that determine the feasibility of mining a particular metallic ore at a certain cite include the quality of useful 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- refining facilities and markets, the metal's supply-versus-demand status, and the environmental impact of the mining and metal processing.

7. The factors that may have influenced the decision to reopen a gold mine inactive for over 100 years may be because more gold was created, or there was a higher demand for gold.

8. What is meant by referring to the quantity of "useful ore" at a site is the amount, usually as a percent, of the desired mineral being mined.

No comments:

Post a Comment