更多"By immersing ore particles in water"的相关试题:
[单项选择]By immersing ore particles in water, ______.
A. we can get ore particles of equal size
B. we can purify aluminum particles
C. we can filter out aluminum
D. we can improve the working conditions around
[单项选择]The particles comprising a given cloud are continually changing, as new ones are added
A B
while others are taking away by moving air.
C D
[单项选择]An unconsolidated aggregate of silt particles is also termed silt, ___________ a consolidated aggregate is called siltstone.
A. ( which
B. ( why
C. ( whereas
D. ( whether
[单项选择]The author states that the smelting of iron ore in England _______.
A. developed rapidly after 1710
B. was controlled by owners of forests
C. helped the sale of cloth
D. was threatened by smelting in America
[单项选择]Galena, the chief ore of lead, is a brittle mineral with a metallic luster.（）
A. hazel
B. dense
C. breakable
D. sparking
[单项选择]Once there is a threat to our water supply water can quickly become the only that matters．
A. 只要水源受到威胁，水很快就会变成惟一重要的物质。
B. 供水一度出现危机，所以水很快就成了惟一紧缺的物质。
C. 供水一旦受到威胁，水很快就会成为惟一至关重要的问题。
D. 有一次水源曾遭受污染，水成了人们惟一不能很快解决的问题。
[单项选择]Ice particles bouncing off hail falling through a cloud acquire______.
A. a negative charge
B. no electric charge at all
C. a positive charge
D. bothA) and
[单项选择]Smoke particles and other air pollutants are often trapped in the atmosphere, thus forming dirty fog.
A. constrained
B. caught
C. concealed
D. concentrated
[单项选择]Brushing removes larger particles, but dentists suggest brushing the back of the tongue as well, where food residues and bacteria ______.
A. flourish
B. collaborate
C. embark
D. congregate
[单项选择]What does "it" of "since water-vapor becomes water when it cools" in Para. 3. refer to
A. Water-vapor.
B. Water.
C. Cloud.
D. Air.
[单项选择]The perpetual spinning of particles is much like that of a top, with one significant difference: unlike the top, the particles have no need to be wound up, for ______ is one of their ______ properties.
A. (A) revolution...radical
B. (B) motion...intangible
C. (C) rotation...intrinsic
D. (D) acceleration...lesser
E. (E) collision...hypothetical
[单项选择]The water-skier ______ over the water.
A. skimmed
B. floated
C. drifted
D. swam
[单项选择]The production of tin ore in the United States is relatively insignificant, _______ less than one hundred tons annually.
A. amounting to
B. in the amount
C. amounts to it
D. to the amount of
[单项选择]DEHYDRATE: WATER::
A. infiltrate : insecurity
B. wither : vitality
C. ossify : strength
D. desecrate : piety
E. contaminate : viability
