What chemicals are added to TSI to detect the production of hydrogen sulfide gas?
A) Phenol red and ferrous sulfate
B) Bromothymol blue and sodium thiosulfate
C) Ferrous sulfate and sodium thiosulfate
D) Copper sulfate and ferrous sulfate

Question

Quizplus · Accepted Answer

Ferrous sulfate and sodium thiosulfate are added to TSI to detect the production of hydrogen sulfide gas. The presence of hydrogen sulfide gas will react with the ferrous sulfate to form a black precipitate. Sodium thiosulfate is added as a reducing agent to prevent false positive results. The other choices do not contain sodium thiosulfate, which is necessary for accurate results.

What Chemicals Are Added to TSI to Detect the Production