A controlled investigation is a experiment that is set for example the same rule for everything
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Answer:
Most similar - Lithium
Least similar - Phosphorus
Explanation:
Rubidium is an element in group 1A of the periodic table. It is a metal and forms an ionic compound with chlorine. The formula of the compound is RbCl.
If we look at the options, Lithium is also a group 1A element and forms an ionic compound with chlorine having the formula LiCl which is very much similar to RbCl chemically.
Phosphorus is a nonmetal. Its compounds with chlorine, PCl3 and PCl5 are covalent and does not resemble RbCl in any way.
Answer:
It gives the number of protons in the nucleus of each atom of that element.
Explanation:
