Synthesis. Which is "<span>Noun. (plural syntheses) The formation of something complex or coherent by combining simpler things. (chemistry) The reaction of elements or compounds to form more complex compounds.".....According to www.dictionary.com.</span>
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Explanation:
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In this case, according to the described chemical reaction, Cl2 replaces iodine in NaI in order to produce I2 and NaCl:

It is possible to realize how chlorine replaces iodine in agreement with the single displacement reaction. Moreover, since chlorine and iodine atoms are not correctly balanced, we add a 2 in front of both NaI and NaCl in order to do so:

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Iron doesn't fit because it doesn't have enough atoms or protons in its nucleus so there for it belongs in column 2. <span />
Answer:
Check the image file attached
Explanation: