<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Precipitate is defined as insoluble solid substance that emerges when two different aqueous solutions are mixed together. It usually settles down at the bottom of the solution after sometime.
For the given chemical equation:

The products formed in the reaction are calcium carbonate and potassium chloride. Out of the two products, one of them is insoluble which is calcium carbonate. Thus, it is considered as a precipitate.
Hence, the correct answer is Option B.
Large samples... also can be small as well but usually bigger is better
Answer:
Molarity of a solution that contains 3.11 mol of NaNO3 is 1,24 M
Explanation:
We understand molarity as the number of moles of solute that are contained in 1 L of solution, then if in a solution of 2.50 L we have 3.11 moles, it remains to calculate how many moles do we have in 1 liter.
2,50 L .......... 3,11 moles
1 L .................. x
X = ( 1 L x 3,11 moles) / 2,50 L = 1,24
It's called "Ionic compound"
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