Answer: A) Mass CaCl2 is 16,65g
B) Excess Reactant is the CaCO3
C) Mass of R Excess eactant is 16,9g CaCO3
Explanation:
A) In order to calculate the Mass of CaCl2, we first check the Equation is actually Balanced, and then we verify which reagent is the limiting one by comparing the amount of product formed with each reactant, and the one with the lowest number is the limiting reactant.
CaCO3(s)+2HCl(aq)⟶CaCl2(aq)+H2O(l)+CO2(g)
Moles produce with 32g CaCO3 ⟶ 32.0g CaCO3 x (1mol CaCO3/100.09g CaCO3)x (1mol CaCl2 /1 mol CaCO3) = 0.32 mol CaCl2
Moles produce with 11 g HCl ⟶ 11.0 g HCl x ( 1mol HCL / 36.46g HCl) x (1 mol CaCl2 /2 mol HCl) = 0.15 mol CaCl2
As we can see the amount of CaCl2 formed with the HCl is the lowest one , therefore the limiting reactant is the HCl. Then, we proceed calculating the mass of CaCl2 from the 11g of HCl.
0.15mol CaCl2 x (110.98 g CaCl2 /1mol CaCl2) = 16.65 g CaCl2
B) The Excess Reagent is the one that produces a larger amount of product that we have previously calculated.
In this case is the CaCO3.
C) In order to estimate the mass of excess reagent, we start by calculating how much CaCO3 reacts with the giving HCl:
11.0 g HCl x (1mol HCL/36.46g HCl) x ( 1 mol CaCO3 / 2 mol HCl)x (100.09 g CaCO3/ 1 mol CaCO3) = 15.10 g CaCO3
That means that only 15.10g CaCO3 will react with 11g of HCl however we were giving 32g of CaCO3, thus, 32g - 15.10g = 16.9g CaCO3 left
