UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper III
Q4(d). Standard-addition calculation
Question
5 mL sample diluted to 100 mL gives A=0.525. Another 5 mL plus 10 mL of 0.05 mg/mL standard, also diluted to 100 mL, gives A=0.635. Find the sample concentration.
Answer in brief
The original sample contains 0.477 mg/mL analyte.
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CoversStandard-addition calculationMatrix compensation
All parts of Question 4
- 4(a) Specific surface area of divided cubes5 marks
- 4(b) Sodium oxide in feldspar10 marks
- 4(c)(i) Preparation and visualisation of TLC plates5 marks
- 4(c)(ii) Alumina as an adsorbent5 marks
- 4(d) Standard-addition calculation5 marks