sea sample 25.00 mL Cl^- ion 0.2970 M AgNO3 53.63 mL mass percent

sea sample 25.00 mL Cl^- ion 0.2970 M AgNO3 53.63 mL mass percent

 

 

어떤 바닷물 시료 25.00 mL 안에 들어있는 Cl^- 이온의 침전 적정에

0.2970 M AgNO3 용액 53.63 mL가 소비되었다면,

Cl^- 이온의 질량 백분율은?

단, 바닷물 밀도 = 1.024 g/mL, Cl의 몰질량 = 35.45 g/mol.

 

 

The mass percent of Cl^- in a seawater sample is determined

by titrating 25.00 mL of seawater with AgNO3 solution,

causing a precipitation reaction.

An indicator is used to detect the end point,

which occurs when free Ag^+ ion is present in solution

after all the Cl^- has reacted.

If 53.63 mL of 0.2970 M AgNO3 is required to reach the end point,

what is the mass percent of Cl^- in the seawater (d of seawater = 1.024 g/mL)?

 

---------------------------------------------------

 

알짜 이온 반응식

Ag^+(aq) + Cl^-(aq) → AgCl(s)

 

 

 

(0.2970 mol/L) (53.63/1000 L) = 0.01593 mol AgNO3

= 0.01593 mol Cl^-

 

 

 

0.01593 mol × (35.45 g/mol) = 0.5647 g Cl^-

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

25.00 mL × (1.024 g/mL) = 25.60 g seawater

 

 

 

%농도 = (용질 질량 / 용액 질량) × 100

( 참고 https://ywpop.tistory.com/2656 )

 

= (0.5647 / 25.60) × 100

= 2.206% w/w

 

 

 

답: 2.206%

 

 

 

 

[키워드] AgCl 침전 적정 기준, AgCl 침전 적정 사전