Serum Chloride Flashcards Preview

Clinical Chemistry Laboratory 2 > Serum Chloride > Flashcards

Flashcards in Serum Chloride Deck (17)
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0
Q

Solution (Standard)

A

5 mL standard NaCl

0.4 mL s-diphenylcarbazone

1
Q

Color of undeteriorated s-diphenylcarbazone

A

Reddish-orange

2
Q

Prepared by adding 0.5 mL 2/3 N sulfuric acid and 0.5 mL 10% sodium tungstate to 1 mL serum and 8 mL distilled water

A

Folin-Wu protein-free filtrate

3
Q

Forms a lavender-colored complex

A

Excess of mercuric ions

4
Q

Reagents

A
1 Mercuric nitrate solution
2 2 N HNO3
3 S-diphenylcarbazone indicator, 0.1%
4 NaCl standard
5 H2SO4, 2/3 N
6 10% sodium tungstate
5
Q

Orange precipitate formed upon dilution

A

Mercuric oxide

6
Q

Reference range for 24 hour urine

A

11-250 mmol/day

7
Q

Titrant

A

Standard mercuric nitrate solution

8
Q

Procedure

A
1 Prepare a Folin-Wu protein-free filtrate
2 Label (2) Erlenmeyer flasks U and S and add solution
3 Using a 2 mL serological pipette, titrate both U and S to the lavender end point with mercuric nitrate solution and record the mL required to obtain the end point for each specimen
9
Q

Indicator

A

s-diphenylcarbazone

10
Q

Stability of indicator if stored in a brown bottle

A

Approx. 3-4 weeks

11
Q

Product of reaction of chloride with mercuric ions

A

Soluble but undissociated mercuric chloride

12
Q

Method

A

Schales and Schales Method

12
Q

Solution (Unknown)

A

5 mL PFF

0.4 mL s-diphenylcarbazone

14
Q

Principle

A

The sample is titrated with standard mercuric nitrate solution at the proper pH, in the presence of an indicator (s-diphenylcarbazone). The chloride present reacts with the mercuric ions in the mercuric nitrate solution to form soluble but undissociated mercuric chloride. When an excess of mercuric ions has been added a lavender-colored complex is formed. This is a mercurimetric procedure utilizing a direct titration.

15
Q

Calculations

A
  1. (mL Hg(NO3)2 required to titrate unknown/mL Hg(NO3)2 required to titrate standard) x 5 mg/mL x 100/0.5 = mg Cl as NaCl/100 mL
  2. Serum Cl = (mg % Cl x 10)/58.5
  3. mg % Cl as NaCl x 10 = mEq/L
16
Q

Reference range for serum, plasma

A

98-107 mmol/L