cations

Question 1

after adding aqueous sodium hydroxide : white ppt, soluble in excess giving a colorless solution

after adding aqueous ammonia : white ppt insoluble in excess

Answer 1

aluminum Al3+

Question 2

after adding aqueous sodium hydroxide : ammonia produced on warming

Answer 2

ammonium (NH4)+

Question 3

after adding aqueous sodium hydroxide : white ppt insoluble in excess

after adding aqueous ammonia : no ppt or very slight ppt

Answer 3

calcium Ca2+

Question 4

after adding aqueous sodium hydroxide : green ppt soluble in excess

after adding aqueous ammonia : green ppt Insoluble in excess

Answer 4

chromium (III) Cr3+

Question 5

after adding aqueous sodium hydroxide : light blue ppt insoluble in excess

after adding aqueous ammonia : light blue ppt, soluble in excess giving a dark blue solution

Answer 5

copper (II) Cu2+

Question 6

after adding aqueous sodium hydroxide : green ppt, insoluble in excess, ppt turns brown near surface on standing

after adding aqueous ammonia : green ppt, insoluble in excess, ppt turns brown near surface on standing

Answer 6

iron (II) Fe2+

Question 7

after adding aqueous sodium hydroxide : red brown ppt Insoluble in excess

after adding aqueous ammonia : red brown ppt Insoluble in excess

Answer 7

iron (III) Fe3+

Question 8

after adding aqueous sodium hydroxide : white ppt soluble in excess giving a colorless solution

after adding aqueous ammonia : white ppt soluble in excess giving a colorless solution

Answer 8

zinc Zn2+