Gold.
untold
Tin is an element that rhymes with chin.
Nickel is an element that rhymes with tickle.
The element that rhymes with "keen" is "tin."
The closest rhymes for "untold" would be unfold and unsold. However, anything that rhymed with "old" would be acceptable, such as behold, bold, cold, gold, strolled, rolled, fold, hold, behold, foretold and controlled, to name a few.
phosphorous
tin
antimony
Phosphorus
The word "cobalt" rhymes with "proballt" and "snowballt."
The answer would be something scientific like "elephants"!!! JK>>
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