Question

use the periodic table to select the element that best fits each of the following descriptions. which elements likely conduct electricity well? check all that apply. chromium iodine carbon calcium osmium complete which element below is least reactive? which element below must be stored in oil because of its reactivity? fluorine chorine sodium gold

Explanation:

Sub - question 1: Which element is least reactive?

Among the elements (assuming common options related to periodic table reactivity trends, like noble gases or less reactive metals; if we consider the context and typical least reactive elements, gold is a noble metal with low reactivity, or if options included noble gases, but from the dropdown in the third question (though not for this), but generally, among metals, gold is less reactive. Also, considering periodic trends: noble gases are least reactive, but if the options here (even if not shown fully, but from the third question's dropdown having gold, and typical least reactive element in such contexts is gold (Au) as it's a noble metal, or if there were noble gases, but given the options in the third question (fluorine, chlorine, sodium, gold), gold is the least reactive as fluorine and chlorine are halogens (very reactive non - metals), sodium is an alkali metal (very reactive metal), and gold is a transition metal with low reactivity.

Alkali metals (like sodium) and some alkaline earth metals are highly reactive with air and water. Sodium (Na) is an alkali metal. It reacts vigorously with air (oxygen and moisture) and water. To prevent this reaction, it is stored in oil (like kerosene or mineral oil) to isolate it from air and water. Fluorine and chlorine are non - metals (halogens) and are stored differently (not in oil). Gold is unreactive and doesn't need to be stored in oil. So sodium is the element that must be stored in oil due to its high reactivity.

Answer:

gold (assuming the dropdown options for the "least reactive" question include gold; if the options were, for example, noble gases like neon, argon etc., but from the given third question's dropdown, gold is the least reactive among fluorine, chlorine, sodium, gold)

Sub - question 2: Which element must be stored in oil because of its reactivity?