<u>Answer:</u> The number of moles of calcium metal required is 2.0 moles.
<u>Explanation:</u>
We are given:
Moles of water reacted = 4.0 moles
The given chemical reaction follows:

By Stoichiometry of the reaction:
2 moles of water is reacted with 1 mole of calcium metal
So, 4.0 moles of water will react with =
of calcium metal
Hence, the number of moles of calcium metal required is 2.0 moles.
<span>The theoretical yield for a reaction is calculated based on the limiting reagent. This allows researchers to determine how much product can actually be formed based on the reagents present at the beginning of the reaction.</span>
<span>The actual yield will never be 100 percent due to limitations.</span>
The object has an overall positive charge.
Answer:
I think its C a scientific journal article
Explanation:
Any kind of journal is considered a primary source because journals contain info that the original author wrote. Encyclopedias are considered teritary sources, but im not sure if that counts ...so id go with journals.
The Answer is D cause of the people going back and forth.