Answer:
(B) II, IV.
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Answer:
Uranium must be purified before it is used as a fuel source
Explanation:
The purer the uranium sample, the more the concentration of uranium in the fuel is.
Whenever uranium is extracted from nature, it contains a lot of impurities. Only a few special nuclear reactors can utilize uranium in this raw state. most of the others have to get uranium to become about 3% pure before they begin using it.
To do this, uranium has to be passed through a series of chemical reactions all with the aim of extracting the other compounds that may be present in the fuel.
The arrangement of the elements in order of decreasing metallic character is: Rb, Zn, P, S, F, Ca, Co, Cr
<h3 /><h3>What are metals?</h3>
Metals are elements which are known by their special ability to form ions by a loss of electrons.
The increasing metallic character of metal is a measure of their ability to lose electrons.
Metallic character increases from right to left and down a group in the period table.
Metals are found to the left of the period table.
In conclusion, metals are known by their ability to lose electrons.
Learn more about metals at: brainly.com/question/25597694
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Answer:
C. because the 4s orbital is at a lower energy level