Answer to Question #335371 in General Chemistry for grey tyrant

Question

The mineral chalk, which is made up of CaCO3 can be prepared by the reaction of solutions of CaCl2 and Na2CO3

a. Write the balance chemical equation

b. What volume of 0.500 M CaCl2 and 0.250 M Na2CO3 must be mixed to precipitate 8.51 g of CaCO3 ?

Answer 1

a. CaCl₂ + Na₂CO₃ = CaCO₃ + 2NaCl

b. m(CaCl₂) = (m(CaCO₃) * Mr(CaCl₂)) / Mr(CaCO₃)

m(CaCl₂) = (8.51 g * 110.98 g/mol) / 100.09 g/mole = 9.44 g

С_m = nV = m/MV; V(CaCl₂) = m(CaCl₂) / C(CaCl₂) / M(CaCl₂)

V(CaCl₂) = 9.44 g / 0.500 M / 110.98 g/mol = 0.17 L

m(Na₂CO₃) = ((m(CaCO₃) * Mr(Na₂CO₃)) / Mr(CaCO₃)

m(Na₂CO₃) = (8.51 g * 105.99 g/mol) / 100.09 g/mole = 9.01 g

С_m = nV = m/MV; V(Na₂CO₃) = m(Na₂CO₃) / C(Na₂CO₃) / MNa₂CO₃)

V(Na₂CO₃) = 9.01 g /0.250 M / 105.99 g/mol = 0.34 L