The grams of MgCO3 that are needed to make 1.2 l of 1.5M MgCl2 solution is calculated as below
MgCO3 +2HCl = MgCl2 +CO2 +H2O
find the moles of MgCl2 produced
moles= molarity x volume
= 1.2 x 1.5 = 1.8 moles
by use of mole ratio between MgCO3 to MgCl2 which is 1:1 the moles of MgCo3 is therefore = 1.8moles
mass of MgCo3 =moles x molar mass
= 1.8moles x 84.3 g/mol= 151.74 grams of MgCO3
Boyles law states P1V1=P2V2
P being pressure and V being volume
So volume and pressure
<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.