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2 years ago

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Consider the reaction. CaCl2(aq)+K2CO3(aq)⟶CaCO3+2KCl. Identify the precipitate, or lack thereof, for the reaction. (A) KCl (B)

CaCO3 (C) no precipitate

1 answer:

Natali5045456 [20]2 years ago

4 0

<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:

$CaCl_2(aq.)+K_2CO_3(aq.)\rightarrow CaCO_3(s)+2KCl(aq.)$

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.

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Thus, there will be 18 $Cr_{2}O_{3}$ units in 1 unit cell.

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Since, volume of sphere is $V=\frac{4}{3}\pi r^{3}$ ,

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The atomic packing factor is ratio of volume of sphere and volume of crystal, thus,

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