How many grams of the salt CaF2 (g) are formed when 15.7 mL of 0.612 M KF reacts with an excess of aqueous calcium bicarbonate (Ca(HCO3)2) via a metathesis reaction?

Respuesta :

Answer:

[tex]m_{CaF_2}0.375gCaF_2[/tex]

Explanation:

Hello,

In this case, for the studied reaction:

[tex]2KF+Ca(HCO_3)_2\rightarrow CaF_2+2KHCO_3[/tex]

Thus, the first step is to compute the reacting moles of potassium fluoride by using its volume and molarity:

[tex]n_{KF}=0.0157L*0.612\frac{mol}{L} =9.61x10^{-3}molKF[/tex]

Then, we apply the 2:1 molar ratio between potassium fluoride and calcium fluoride to compute the produced moles of calcium fluoride:

[tex]n_{CaF_2}=9.61x10^{-3}molKF*\frac{1molCaF_2}{2molKF} =4.80x10^{-3}molCaF_2[/tex]

Finally, by using the molar mass of calcium fluoride (78.07 g/mol) we can compute its produced grams:

[tex]m_{CaF_2}=4.80x10^{-3}molCaF_2*\frac{78.07gCaF_2}{1molCaF_2} \\\\m_{CaF_2}0.375gCaF_2[/tex]

Best regards.