unk9scheme[1](2) - Instruction for unknown 9A/9B The author...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Instruction for unknown 9A/9B The author is not responsible for the scheme! Possible ions: 1. Cations: Na + , K + , NH 4 + , Ca 2+ , Mg(OH 2 ) 6 2+ , Al(OH 2 ) 6 3+ Zn(OH 2 ) 6 2+ , Ag(OH 2 ) 2 + , Cu(OH 2 ) 6 2+ 2. Anions: HO - , CO 3 2- , HCO 3 - , SO 4 2- , HSO 4 - , NO 3 - , Cl - , HS - , O 2- 3. Possible insoluble substance: Ca(OH) 2 , CaSO 4 •2H 2 O, CaCO 3 , MgCO 3 , Mg(OH) 2 AgCl, Ag 2 O, Ag 2 CO 3 , Ag 2 S, Ag 2 SO 4 , ZnS, ZnCO 3 , Zn(OH) 2 , CuO, CuS, CuCO 3 4. Alums Notes:: Notes: --9A (the sample with the numerical label) is a pure salt , which means it only contains two (one cation and one anion) or three ( alums , i.e., two cations and SO 4 2− ) ions. -- The insoluble substance could be one or more kinds of the above compounds. They will not issue Zn(OH) 2 / ZnS in the same sample, nor would a MgCO 3 / Mg(OH) 2 be issued. Tests on original sample Flame o Yellow-orange: Na + o Red-orange (HCl) : Ca 2+ o Purple: K + o Green: Cu(OH 2 ) 6 2+ o None: NH 4 + , Mg(OH 2 ) 2+ , Al(OH 2 ) 3+ , Zn(OH 2 ) 2+ , Ag(OH 2 ) 2 + NH 4 + Test o Place small sample in test tube, add 1 M (or 6M) NaOH, suspend damp red litmus over it, if it turns blue, NH 4 + is present CO 3 2- /HCO 3 - Test o Place original sample in a spot plate and add a few drops of 1M HNO
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

unk9scheme[1](2) - Instruction for unknown 9A/9B The author...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online