silicates, and, like all silicate minerals, they are
15 refractory, resistant to analysis, and extremely difficult to
process. The aluminum silicates are therefore generally
unsuitable alternatives to bauxite because considerably
more energy is required to extract alumina from them.
4. The author implies that a mineral must either be or readily supply which of the following in order to be classified as an aluminum ore?
An aggregate
Bauxite
Alumina
Corundum
An aluminum silicate
For the following question, consider each of the choices separately and select all that apply
5. The passage supplies information for answering all of the following questions regarding aluminous minerals
A Are aluminum-bearing nonbauxite minerals plentiful?
B Do the aluminous minerals found in bauxite contain hydrated oxides?
□C Are aluminous hydrated oxides found in rocks?
6. The author implies that corundum would be used to produce aluminum if
corundum could be found that is not contami-nated by silicates
the production of alumina could be eliminated as an intermediate step in manufacturing alu-minum
【新gre逻辑阅读 每日一练17】相关文章:
最新
2016-03-01
2016-03-01
2016-03-01
2016-03-01
2016-03-01
2016-03-01