Chem Lab 1 Study Sheet

Question 1

silver is ____ in aqueos solution

Answer 1

colorless

Question 2

lead is ____ in aqueous solution

Answer 2

colorless

Question 3

mercury is ____ in aqueous solution

Answer 3

colorless

Question 4

Ag+ (aq) + Cl- (aq) —> ?

Answer 4

AgCl (white)

Question 5

Pb^2(aq) + 2Cl-(aq) –> ?

Answer 5

PbCl2 (white)

Question 6

Hg2^2+(aq) + 2Cl-(aq) —> ?

Answer 6

Hg2Cl2 (white)

Question 7

immediate formation of a yellow percipitate of lead chromate confirms the presense of ____ original solution

Answer 7

Pb^2+

Question 8

cation is an ____ complex ion Ag+

Answer 8

ammonia

Question 9

silver chloride dissolves in aqueous ammonia forming a ___

Answer 9

soluble, colorless compound

Question 10

when reaction produces black color ____ is present

Answer 10

mercury (Hg)

Question 11

when HgCl2 comes in contact with aqueous ammonia undergoes an oxidation reduction reaction forming percipitates of ____

Answer 11

finely divided elemental mercury, Hg (black) and mercury (II) amide chloride, HgNH2Cl (white)

Question 12

appearance of a dark gray to black percipitate confirms presence of ____

Answer 12

Hg2^2+ = mercury (II)

Question 13

if silver ion present, centrate from procedure I-C contains _____

Answer 13

soluble ammonia complex of silver chloride

Question 14

destroying this complex with nitric acid will bring the formation of ____ percipitate confirming presence of Ag+

Answer 14

silver chloride

Question 15

appearance of a white percipitate confirms the presence of ____

Answer 15

Ag+

Question 16

describe iron

Answer 16

• Fe^2+
• pale green in aqueous solution
• Fe^3+
• colorless in dilute HNO3
• yellow in HCL

Question 17

describe chromium

Answer 17

• Cr^2+
• bright blue in aqueous solution
• Cr^3+
• dark blue violet in aqueous solution

Question 18

describe cobalt

Answer 18

• CO^2+
• red-pink in aqueous solution

Question 19

describe zinc

Answer 19

• Zn^2+
• colorless in aqueous solution

Question 20

yellow centrate suggests presence of ____

Answer 20

CrO4^2-

Question 21

formation of a dark blood red solution confirms presence of ____

Answer 21

Fe^3+

Question 22

rapid formation of yellow precipitate of lead chromate confirms presence of ____

Answer 22

chromium(III) in original solution