A student is given a sample in lab that contains one of the ions listed below.After adding a few drops of AgNO₃ solution to a portion of the unknown sample,the student observed a grayish precipitate.After adding a few drops of Mg(NO₃)₂ solution to another portion of the unknown sample,the student got a black precipitate.Based on these observations,what is the only possible ion in this student's sample?

Question

Quizplus · Accepted Answer

The grayish precipitate with AgNO3 indicates the presence of a halide ion, and the black precipitate with Mg(NO3)2 suggests the formation of MgS, which is characteristic of the sulfide ion (S^2-). Therefore, the only possible ion that matches these observations is the sulfide ion (S^2-), which is option D.

A Student Is Given a Sample in Lab That Contains