Verified Solution • 2025–26 Session
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QJEEM18Cha0d0: JEE Main 2018 Chemistry - Class 12 JEEM18Cha0d0 Solution: The incorrect statement is :
The incorrect statement is :
Multiple Choice Options
- A Cu2+ salts give red coloured borax bead test in reducing flame.
- B Cu2+ and Ni2+ ions give black precipitate with H2S in presence of HCl solution.
- C Ferric ion gives blood red color with potasium thiocyanate.
- D Cu2+ ion gives chocolate coloured preciitate with potassium ferrocyanide solution.
Step-by-Step Verified Solution
Cu2+ and Ni2+ ions belong to Group II and Group IV respectively.
Group II sulphides precipitated out even under low concentration of sulphides, while Group IV sulphides require higher concentration of sulphides. To fulfill this reaction condition, dil. HCl is chosen in Group II reagents and NH4OH is chosen in Group IV reagents.