CaC2O4 0.104 M CaCl2 37.5 mL Na2C2O4

CaC2O4 0.104 M CaCl2 37.5 mL Na2C2O4

 

 

Calcium oxalate, CaC2O4, is very insoluble in water.

What mass of sodium oxalate, Na2C2O4, is required

to precipitate the calcium ion

from 37.5 mL of 0.104 M CaCl2 solution?

 

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(0.104 mol/L) (37.5/1000 L) = 0.00390 mol CaCl2

( 참고 https://ywpop.tistory.com/7787 )

 

 

 

CaCl2(aq) → Ca^2+(aq) + 2Cl^-(aq)

CaCl2 : Ca^2+ = 1 : 1 계수비(= 몰수비) 이므로,

CaCl2의 몰수 = Ca^2+의 몰수 = 0.00390 mol

 

 

 

Ca^2+(aq) + C2O4^2-(aq) → CaC2O4(s)

Ca^2+ : C2O4^2- = 1 : 1 계수비(= 몰수비)

 

 

 

Na2C2O4(aq) → 2Na^+(aq) + C2O4^2-(aq)

Na2C2O4 : C2O4^2- = 1 : 1 계수비(= 몰수비)

 

 

 

C2O4^2-의 몰수 = Na2C2O4의 몰수 = 0.00390 mol

 

 

 

Na2C2O4의 몰질량 = 133.9985 ≒ 134.00 g/mol 이므로,

0.00390 mol × (134.00 g/mol) = 0.5226 g Na2C2O4

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

답: 0.523 g