Print version Updated: 31 March 2020 Lecture #37 Precipitation and - - PowerPoint PPT Presentation

▶
print version
SMART_READER_LITE
LIVE PREVIEW

Print version Updated: 31 March 2020 Lecture #37 Precipitation and - - PowerPoint PPT Presentation

May 23, 2023 192 likes •354 views

Print version Updated: 31 March 2020 Lecture #37 Precipitation and Dissolution: Metal Hydroxides/Oxides & Carbonates (Stumm & Morgan, Chapt.7) Benjamin; Chapter 8.7-8.15 David Reckhow CEE 680 #37 1 Practice Session Al(OH) 3

slide-1
SLIDE 1

Lecture #37 Precipitation and Dissolution: Metal Hydroxides/Oxides & Carbonates

(Stumm & Morgan, Chapt.7)

Benjamin; Chapter 8.7-8.15

David Reckhow CEE 680 #37 1

Updated: 31 March 2020

Print version

slide-2
SLIDE 2

Practice Session

Al(OH)3 ppt

 Homework

Cr(OH)3 ppt Zn(OH)2 ppt Cd(OH)2 ppt

David Reckhow CEE 680 #37 2

slide-3
SLIDE 3

Metal Precipitates; Kso values (1/2)

 Table 11.1a in Benjamin (pg 581)

David Reckhow CEE 680 #37 3

slide-4
SLIDE 4

Metal Precipitates; Kso values (2/2)

 Table 11.1b in Benjamin (pg 582)

David Reckhow CEE 680 #37 4

slide-5
SLIDE 5

Metal Hydrolysis

 Table 10.2 in

Benjamin

 Pg 858-859

David Reckhow CEE 680 #37 5

slide-6
SLIDE 6

Cd(OH)2 example

 Cd species equations

 From Benjamin, pg 584

David Reckhow CEE 680 #37 6

slide-7
SLIDE 7

Cd(OH)2 solubility diagram

 Pg 586 in Benjamin

David Reckhow CEE 680 #37 7

slide-8
SLIDE 8

Zinc with OH, CO3 and Cl

 Pg 636 in Benjamin

David Reckhow CEE 680 #37 8

slide-9
SLIDE 9

 Zn solubility  Compare to Stumm &

Morgan’s fig. 6.8c, pg.273

David Reckhow CEE 680 #37 9

pH

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Log C

  • 14
  • 13
  • 12
  • 11
  • 10
  • 9
  • 8
  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

H+

OH-

Zn+2 Zn(OH)4

  • 2

ZnOH+ Zn(OH)2 (aq) Zn2(OH)6

  • 2

ZnTotal Zn(OH)3

  • Zn2(OH)+3

Zn(OH)2

slide-10
SLIDE 10

David Reckhow CEE 680 #37 10

Stumm & Morgan, 1996, Figure 7.6a, pg. 370

ZnO solubility

slide-11
SLIDE 11

 With oxalate

 10-4 M

David Reckhow CEE 680 #37 11

Stumm & Morgan, 1996, Figure 7.6b, pg. 370

ZnO solubility

slide-12
SLIDE 12

David Reckhow CEE 680 #37 12

pH

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Log C

  • 14
  • 13
  • 12
  • 11
  • 10
  • 9
  • 8
  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

H+

OH-

Fe+3 Fe(OH)4

  • FeOH+2

Fe(OH)2

+

Fe2(OH)2

+4

FeTotal

slide-13
SLIDE 13

Fe with EDTA

 10-8 M EDTA

 Elevates

solubility in mid-pH range

David Reckhow CEE 680 #37 13

Stumm & Morgan, 1996, Figure 7.7a, pg. 371

slide-14
SLIDE 14

Fe with EDTA & Ca

 10-8 M EDTA  10-2 M Ca

 Mostly

counteracts affect of EDTA

David Reckhow CEE 680 #37 14

Stumm & Morgan, 1996, Figure 7.7b, pg. 371

slide-15
SLIDE 15

To next lecture

David Reckhow CEE 680 #37 15