CHEM 302 LIBERTY UNIVERSITY Report P2 Organic Sulfide_SUMMARIES_2023.pdf

ABSTRACT

An experiment entitled “Anion Analysis” has been carried out with the

aim of being able to identify anions in 'unknown' solutions and solids using the

'liquid chemistry' separation method which is based on the behavior of different

ions when reacted with certain reagents. The principle used is a specific reaction

and ion selective. And the method used is the separation of 'liquid chemistry'. The

results obtained are:

- Cl reacted with cloudy white AgNO + HNO , white precipitate

- solution 3 3 

- Br solution reacted with AgNO + HNO clear solution , no precipitate

- 3 3 

- Solution I reacted with AgNO + HNO cloudy white solution

- 3 3 

- SO and SO

3 - 4 2- solutions reacted with Ba (C 2 2

H O ) clear solution of

2 2 

white precipitate in SO solution and cloudy solution has no precipitate in

3 -

SO 4 2- solution

- CrO 4 2- solution reacted with Ba (C 2 2 2 2

H O ) + OH brick red solution

-

- PO solution reacted with Ba (C H O ) + HCl cloudy solution and

4 3- 2 2 2 2 

there was a white precipitate

- NO reacted with concentrated H SO plus Ba (C H O )

3 solution - 2 4 2 2 2 2

cloudy solution

- Unknown solution formed a cloudy solution and there was a white

precipitate and it was identified as belonging to the calcium-barium group.

Keyword: anion, analysis, liquid chemistry, specific, selective.

EXPERIMENT II

ANION ANALYSIS

I. OBJECTIVES OF THE EXPERIMENT

Can identify anions in 'unknown' solutions and solids using 'liquid chemistry'

separation methods which are based on the behavior of different ions when

reacted with certain reagents.

II. LITERATURE REVIEW

2.1 Qualitative Analysis

Qualitative analysis is a work process in detecting the presence of a

chemical element in an unknown sample. Qualitative analysis is one of the

most effective ways to study chemistry and the elements and ions present in

a solution. In the qualitative analysis method several reagents are used,

including group reagents and also specific reagents, these two reagents are

used to determine the type of anion or cation present in a solution. The class

regimens used for the most common classification of cations are

hydrochloric acid, hydrogen sulfide, ammonium sulfide, and also

ammonium carbonate. This classification itself is based on whether a cation

can react with these reagents by forming a precipitate or not forming a

precipitate. Meanwhile, the method used for anions is not as systematic as

for cations. However, the scheme used is not a rigid one, because anions

also belong to more than one group (Keenan 1992) .

2 .2 Precipitation Method

The precipitation method is the process of forming a precipitate, where the

precipitate obtained occurs from self-separation as a solid phase out of

solution. The precipitate may be crystalline (crystalline) or colloidal, and

can be removed from solution by filtration or centrifugation. A precipitate

forms if the solution becomes oversaturated with the substance in question.

The solubility(s) of a precipitate is, by definition, equal to the molar

concentration of the saturated solution. Solubility depends on various

conditions such as temperature, pressure, the concentration of other

substances in the solution and on the composition of the solvent (Svehla

1985d) .

2.3 Solubility Product

The solubility product (Ksp) value of a poorly soluble ionic compound

can provide information about the solubility of a compound in water. The

greater the Ksp value of a substance, the more soluble the compound is. The

Ksp value of a substance can be used to predict whether a substance will

precipitate if two solutions containing ions from poorly soluble compounds

are mixed. Solubility is the ability of salts to dissolve in water. The ability of

each salt to dissolve in water is not the same, there are salts that dissolve

easily in water such as sodium chloride and there are salts that are difficult

to dissolve in water such as silver chloride (AgCl) . The Ksp of a compound

can be determined from laboratory experiments by measuring solubility (the

mass of a compound that can dissolve in each liter of solution) until it is

exactly saturated. In that state, the ability of the solvent has been maximized

to dissolve or ionize the solute. Excess dissolved substance even a little will

be a precipitate. The solubility product in its actual state is the final value

attained by the product of ions when equilibrium is reached between the

solid phase of the only slightly soluble salt and the solution (Syukri 1999) .

if the silver chloride precipitate is in equilibrium with the saturated

solution, then the equilibrium is:

AgCl Ag + Cl

+ -

and Cl ions are present in the solid phase. The equilibrium constant

can be written as:

   

 

AgCl

Ag



The concentration of silver chloride in the solid phase does not change

and therefore can be entered into a new constant. Ksp is called the solubility

product:

   



ClAgKsp

So in a solution of silver chloride, at constant temperature and

pressure, the product of the concentrations of silver ions and chloride ions is

constant. For a saturated solution of an electrolyte Ava vb

, B which ionizes

into the ions A and B

va m- vb n-

A B

va vb

The solubility product [K] can be expressed as:

   

BAKsp





So it can be stated that in a saturated solution of a slightly soluble

electrolyte, the product of the concentrations of the constituent ions for any

given temperature is constant, with the ion concentration raised to a number

equal to the number of individual ions produced by the dissociation of an

electrolyte molecule. (Svehla 1985d) .

2.4 Sludge Washing

Washing the precipitate aims to remove contamination (impurities) on

the surface of the precipitate. Washing the precipitate uses a strong

electrolyte solution containing the same ion as the precipitate so that the

solubility of the precipitate decreases. The solution must be volatile so that

the precipitate is easy to weigh. Washing solutions are divided into 3 groups,

namely:

1. Solutions that can reduce the solubility of the precipitate

2. Solutions that can prevent the hydrolysis of salts from weak bases

or weak acids

3. A solution that can prevent the formation of colloids which can

result in passing on filter paper (Svehla 1985d) .

2.5 Complex Formation Reactions

Coordination compounds/complex compounds are compounds that are

formed through a complex formation reaction and a coordination bond

occurs, namely a coordination covalent bond between the central ion/atom

and the ligand (protecting group). Also known as complex compounds

because it is difficult to understand at the beginning of its discovery. The

coordinate covalent bond that occurs is a covalent bond (there are shared

pairs of electrons) in which the shared pair of electrons comes from one of

the atoms. Coordination bonds can exist in the cation or anion of the

compound. The central ion/atom is the ion/atom part of the coordination

compound which is in the center (middle part) as the acceptor of the

electron pair so that it can be referred to as a Lewis acid, generally in the

form of metals (especially transition metals). Meanwhile, a ligand or

protective group is an atom/ion part of a coordination compound that is on

the outside as a donor of electron pairs so that it can be referred to as a

Lewis base (R. Chang 2004) .

2.6 Ion Selectivity

Is a reaction that occurs on a group of materials/ions that are different,

for example when Cl- ions are added to cations, a precipitate can occur. This

reaction is not specific, because what can precipitate with Cl- is not only

one type of cation, but three kinds, namely Ag+, Pb+, Hg+, (more, if you

pay attention to other less common cations such as Cu+.Pt4+, Tl+) ( Svehla

1985d) .

2 .7 Liquid Chemistry

Liquid chemistry is a separation method in the analysis of cations and

anions which is based on the behavior of different ions when a solution of

anions or cations is reacted with certain reagents (Svehla 1985d) .

2.8 Anion analysis

Anions are negative ions that are formed when a nonmetal atom gains

one or more electrons. Anions are so named because they are attracted to the

anode (positive field) in an electric field. Atoms usually gain electrons so

they will have an electron configuration like a noble gas. All the elements in

group 17 have seven valence electrons because of their outermost ns2np5

configuration. Therefore, each element will gain one electron and become

an anion with a -1 charge. Likewise, Group 16 elements form ions with a -2

charge, and Group 15 nonmetals form ions with a -3 charge. The anion test

was carried out after the cation test (Svehla 1985d) .

a. In general, anions can be classified based on their properties as

follows:

1. Silver group : The anions precipitated by Ag are Cl, Br, I, and CNS

2 anions. Group calcium-barium : Anion precipitated by Ca2+ and Ba2+,

at a certain pH, namely SO42-, PO42-, CrO42-, C2O42-

3 anions. Dissolved group : Anion that is not easily precipitated namely

NO3- .

4. Volatile acid groups: namely groups that produce gas during

acidification

(DY Chang 1996) .

2.8.1 chloride

Most chlorides are soluble in water, mercury chloride, silver chloride, these

are very slightly soluble in cold water, but easily soluble in hot or boiling

water. CuCl, BiOCl, SbOCL, HgOCl are insoluble in water. Sensitivity 1.5

mg Cl¯ (concentration limit 1 in 30,000) and 0.3 mg Cl¯ (concentration

limit 1 in 150,000) (Svehla 1985d) .

2.8.2 Bromide

Solubility Ag, Hg, Cu, insoluble in water. Lead bromide is very slightly

soluble in cold water, but more soluble in boiling water. All other bromides

are soluble. Sensitivity 2 mg Br (concentration limit of 1 in 25,000)

(Svehla 1985d) .

2.8.3 Iodide

The solubility of iodide is similar to that of chloride and bromide. Silver,

mercury(II), copper(I) and lead iodide are sparingly soluble salts. Sensitivity

2 mg I (concentration limit of 1 in 20,000) (Svehla 1985d) .

2.8.4 Nitrate

All nitrates are soluble in water, the nutrates of mercury and bismuth yield

basic salts when treated with water. These salts are soluble in dilute nitric

acid. Sensitivity 0.05 mg Nitrate with a concentration limit of 1 in 1 million

(Svehla 1985d) .

2.8.5 Sulfate

The sulfates of barium, strontium and lead are practically insoluble in water.

The sulfates of mercury(II) and calcium are sparingly soluble and most of

the sulfates of the remaining metals are soluble (Svehla 1985d) .

2.8.6 Chromate

Metallic chromates are usually colorless solids that give a yellow solution

when dissolved in water. Dilute mineral acids, i.e. hydrogen ions,

chromates, turn into dichromates (Svehla 1985d) .

2.8.7 Phosphates

Phosphates of ammonium and of the alkali metals, except of water-soluble

lithium; Primary phosphates of the alkaline earth metals are also soluble. All

other metal phosphates, as well as the secondary and tertiary phosphates of

the alkaline earth metals, are very sparingly soluble or insoluble in water

(Svehla 1985d) .

2.9 Material Analysis

2.9.1 Aquadest

Physical Properties Chemical

Properties

Liquid form

Colorless

No smell

Boiling point 100 C

Freezing point 0 C

Compounds with the

formula H O

Weak electrolytes

pH = 7 (neutral)

(Basri 2000) .

2.9.2 HCl

Physical Properties Chemical Properties

Liquid

Colorless

Boiling point 50.0 C

Melting point -25 C

Molecular weight 36.46

g/mol

Vapor pressure 25 kPa at

25 C

pH 0.1

Corrosive

Stable under normal

conditions

(MSDS, 2012) .

2.9.3 H2SO4 _

_ _

Physical Properties Chemical Properties

Clear liquid form

No smell

Boiling point 337 C

The molar mass is 98.08

g/mol

Soluble in water

Strong Acidic

Melting point 10 C

Density 1.84 g/cm 3

(MSDS, 2012).

2.9.4 HNO 3

Physical Properties Chemical Properties

Colorless

No smell

Boiling point 83 C

Melting point 4.1 C

Density 1.84 g/cm 3

Corrosive

Acidic

As an oxidizing agent

(Basri 1996) .

2.9.5 AgNO3

Physical Properties Chemical Properties

Colorless

Solid (crystalline)

Boiling point 97 C

Melting point 59 C

Density 1.82 g/cm 3

Soluble in dilute nitric

acid

Analytical Reagents

(Daintith 1994) .

2 .9.6 Ba(C H O )

2 3 2 2

Physical Properties Chemical Properties

Colored white

No smell

Granular solid form

Relative density 2.02 g/cc

Stable under normal

circumstances

pH 7-8.5

water soluble

(MSDS, 2015).

III. EXPERIMENT METHOD

3.1 Tools and Materials

3.1.1 Tools

1. Test tube

2. Drop pipette

3. Spiritual Heater

4. Clamp

3.1.2 Materials

1. Aquadest

2. HCl

3. HNO 3

4. H2SO4 _

_ _

5. AgNO 3

6. FeSO 4

7. Ba(C H O )

2 3 2 2

3.3 Work Scheme

3.3.1 Chloride Ion Test

-Tests 1 and 2

-test 3

5 tetes larutan Cl-

Tabung reaksi

Hasil

Pengamatan larutan

Penambahan 5 tetes H pekat

2SO4

Hasil

5 tetes larutan Cl-

Tabung reaksi

Penambahan 5 tetes AgNO3

Hasil

Penambahan 5 tetes HNO3

-test 4

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan Cl-

3.1.2 Bromide Ion Test

-Tests 1 and 2

-test 3

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Tabung reaksi

5 tetes larutan Br-

Hasil

Penambahan 5 tetes H2SO4 pekat

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan Br-

-test 4

3.1.3 Iodine Solution Test

-Tests 1 and 2

Hasil

Penambahan 5 tetes H pekat

2SO4

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan I-

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan Br-

-test 3

-test 4

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan I-

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Tabung reaksi

5 tetes larutan I-

3.1.4 Sulfite Ion Test

-Tests 1 and 2

-test 3

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Tabung reaksi

5 tetes larutan SO3-

Hasil

Penambahan 5 tetes H pekat

2SO4

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan SO3-

-test 4

3.1.5 Sulfate Ion Test

-Tests 1 and 2

Hasil

Penambahan 5 tetes H pekat

2SO4

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan SO42-

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan SO3-

-test 3

-test 4

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan SO42-

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Tabung reaksi

5 tetes larutan SO42-

3.1.6 Phosphate Ion Test

-Tests 1 and 2

-test 3

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Tabung reaksi

5 tetes larutan PO43-

Hasil

Penambahan 5 tetes H pekat

2SO4

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan PO43-

-test 4

3.1.7 Nitrate Ion Test

-Tests 1 and 2

-test 3

Tabung reaksi

5 tetes larutan NO3-

Hasil

Penambahan 5 tetes H pekat

2SO4

Hasil

Pengamatan larutan

Tabung reaksi

5 tetes larutan NO3-

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan PO43-

-test 4

3.1.8 Chromate Ion Test

-Tests 1 and 2

Pengamatan larutan

Tabung reaksi

5 tetes larutan CrO42-

Hasil

Penambahan 5 tetes HCl

Hasil

Penambahan 5 tetes Ba(CH3COO)2

Tabung reaksi

5 tetes larutan NO3-

Hasil

Penambahan 5 tetes HNO3

Hasil

Penambahan 5 tetes AgNO3

Hasil

Penambahan 5 tetes H pekat

2SO4

-test 3

-test 4

Hasil

5 tetes larutan CrO42-

Tabung reaksi

Penambahan 5 tetes AgNO3

Hasil

Penambahan 5 tetes HNO3

Hasil

5 tetes larutan CrO32-

Tabung reaksi

Penambahan 5 tetes Ba(CH3COO)2

Hasil

Penambahan 5 tetes HCl

Hasil

3.1.9 Unknown Solution Test

-Tests 1 and 2

-test 3

-test 4

5 tetes larutan sampel

Tabung reaksi

Hasil

Pengamatan larutan

Penambahan 5 tetes H pekat

2SO4

Hasil

5 tetes larutan sampel

Tabung reaksi

Penambahan 5 tetes AgNO3

Hasil

Penambahan 5 tetes HNO3

5 tetes larutan sampel

Tabung reaksi

Penambahan 5 tetes Ba(CH3COO)2

Hasil

Penambahan 5 tetes HCl

Hasil

IV. OBSERVATION DATA N

IV.1 Experimental Data

Ion

Tested

solution

test 1 test 2 test 3 test 4

Solution

Appearan

Concen

trated

H 2 SO

AgNO HNO

3 3

Ba(C H

2 3

O )

2 2

HCl

Cl -Clear

solution

Turbid

solution

, Hot

Turbid

solution,

white

precipitat

Turbid

solution,

white

precipitate

Murky

white

Murky

white

Brother -Yellow

solution

Clear

solution

, Hot

Clear

solution,

precipitat

Clear

solution,

precipitate

Clear

solution

Clear

solution

I- _Clear

solution

Yolk

precipit

ate , hot

White

cloudy

solution

White

cloudy

solution

Clear

solution

Clear

solution

SO 3 2- Clear

solution

Turbid

solution

, hot

Clear

solution

White

Precipita

Clear

solution

White

precipitate

cloudy

white

The

solution

is cloudy

white

SO 4 2- Clear

solution

Clear

solution

tempera

ture

rises

Clear

solution

White

precipitat

Turbid

solution,

precipitate

The

solution is

cloudy

white

The

solution

is cloudy

white and

n there is

a white

precipitat

PO 4 3- Clear

solution

Clear,

hot

solution

Clear

solution

Yellow

precipitat

Clear

solution

Yellow

precipitate

Turbid

solution

and white

precipitate

Turbid

solution

and white

precipitat

NO 3- Yellow

solution

Yellow

solution

, hot

Yellow

solution

Clear

solution

Murky

solution

Murky

solution

CrO 4 2- Yellow

solution

Orange

solution

Brick red

solution

Clear

yellow

Brick red

solution

Brick red

solution

, hot

Unknow

solution

Clear

solution

Clear

solution

tempera

ture

Clear

solution

Clear

solution

Turbid

Solution

solution

with

white

precipitat

Ion

Tested

solution

test 1 test 2 test 3 test 4

Solution

Appearan

Concen

trated

H 2 SO

AgNO HNO Ba(C H

3 3 2 3

O )

2 2

HCl

Cl -Clear

solution

Clear

solution

, Hot

Turbid

solution,

white

precipitat

Turbid

solution,

white

precipitate

White

precipitate

White

precipitat

Brother -Yellow

solution

Clear

solution

, Hot

Clear

solution,

precipitat

White

cloudy

solution

with

yellowish

white

precipitate

White

precipitate

White

Precipitat

I- _Clear

solution

Yolk

precipit

ate , hot

White

cloudy

solution

White

cloudy

solution ,

precipitate

White

precipitate

White or

yellow

precipitat

SO 3 2- Clear

solution

Clear

solution

, hot

Clear

solution

White

Precipita

Clear

solution

White

precipitate

White

precipitate

White

Precipitat

SO 4 2- Clear

solution

Clear

solution

tempera

ture

rises

Murky

solution

White

precipitat

Turbid

solution,

white

precipitate

White

precipitate

White

precipitat

IV.2 Data sesuai Literatur

PO 4 3- Clear

solution

Clear,

hot

solution

Clear

solution

Yellow

precipitat

Clear

solution

Yellow

precipitate

White

precipitate

Turbid

solution

and white

precipitat

NO 3- Yellow

solution

Yellow

solution

, hot

Clear

solution

Murky

solution

The

solution

has no

precipitate

The

solution

has no

precipitat

CrO 4 2- Yellow

solution

Orange

solution

, hot

brownish

red

precipitat

The

precipitate

dissolves

White or

yellow

precipitate

White or

yellow

precipitat

V. hypothesis

An experiment entitled “Anion Analysis” has been carried out , the

purpose of this experiment is to be able to identify anions in 'unknown'

solutions and solids using the 'liquid chemistry' method which is based on

the behavior of different ions when directed with reagents. certain

reagents. The method used is liquid chemical separation based on the

behavior of different ions when reacted with certain reagents. The

principle is based on specific reactions and ion selective. Specific reactions

are the addition of a material or reagent that can only react with one

particular ion (Harjadi 1990) . Ion selective reaction is the addition of a

reagent that reacts on a group of different ions (Harjadi 1990) . The results

to be obtained from this experiment are:

- solution reacted with AgNO + HNO to produce a white precipitate

3 3

Br reacted with AgNO + HNO to produce a yellowish white

- solution 3 3

precipitate

Solution I reacted with AgNO + HNO to produce a yellow precipitate

- 3 3

SO and SO react with Ba (C H O ) to produce a white

3 - 4 2- solutions 2 2 2 2

precipitate

3 2 4 plus FeSO 4

- solution reacted with concentrated H SO to produce a brown

ring .

CrO reacts with Ba (C H O ) + OH produces a white

4 2- solution 2 2 2 2 -

precipitate

PO reacted with Ba (C H O ) + HCl to produce a cloudy

4 3- solution 2 2 2 2

solution

VI. Discussion

An experiment "Anion Analysis" has been carried out with the aim of

being able to identify anions in 'unknown' solutions and solids using the

'liquid chemistry' method which is based on the behavior of different ions

when directed with certain reagents. The method used is liquid chemical

separation based on the behavior of different ions when reacted with

certain reagents. The principle is based on specific reactions and ion

selective. Specific reactions are the addition of a material or reagent that

can only react with one particular ion (Harjadi 1990) . Ion selective

reaction is the addition of a reagent that reacts on a group of different ions

(Harjadi 1990) .

6.1 Test for Chloride Ion in Sodium Chloride

This test aims to determine the presence of Cl in NaCl solution

- anion

using the liquid chemistry method. The solution is a clear solution. Then do

test 2 by adding H SO which aims to acidify the solution. The solution

2 4

becomes cloudy and heat arises. The emergence of this heat indicates that in

the solution an exothermic reaction occurs, in which the solution releases

heat or energy from the system to the surroundings. The system releases

hydrochloric acid into the environment,

The reaction that occurs is :

Cl + H SO

- (aq) 2 4 (aq) (aq) 4

→ HCl + HSO - (aq)

(Svehla 1985c) .

Next, test 3 was carried out by adding AgNO to the solution. This

addition aims to precipitate Cl as AgCl. After this addition the solution

remains cloudy but produces a white precipitate as Cl precipitate.

Precipitation occurs because the price of Qc > Ksp, and the solution is a

saturated solution.

The reaction that occurs :

HCl + AgNO → AgCl + HNO

(aq) 3(aq) (s) 3 (aq)

(Svehla 1985c) .

Next is adding HNO which aims to dissolve AgCl in solution. After

the addition of HNO3 the solution did not change where the solution

, ,

remained cloudy and a precipitate formed. This shows that AgCl in solution

is stable, so it is not easy to break the bond. HNO in this case cannot

dissolve AgCl because of the low concentration of HNO . So, in this test

3 .

the addition of HNO aims to strengthen the identification that the presence

of Br forms AgBr precipitates that are insoluble with dilute HNO .

- ions 3

The reaction

HNO + AgCl →AgCl + NO + H O

3 ( aq) (aq) (s) 3 (aq)

- 2 (l)

(Svehla 1985c) .

Then the solution was tested with test 4, namely by using Ba(C H O

2 3 2

) and HCl. In this case the solution turns cloudy white. This is due to the

stability of AgCl in solution, so it is quite difficult to break the bond. In this

case it can be seen that in the final test the solution is cloudy white, which

indicates a positive result, this is because the color of the cloudy white

solution is close to the formation of a white precipitate. The possibility that

what is happening is the lack of Cl ions contained in the solution or the

solution has not been saturated and the product of the ions has not exceeded

the Ksp value so that a white precipitate has not formed.

6.2 Bromide Ion Test in Potassium Bromide

This experiment aims to identify bromide ions in KBr using liquid

chemistry methods based on the differences in ion behavior when reacted

with certain reagents. In the first test, pay attention to the appearance of the

solution and the result is a yellow solution. The second test, the addition of

H SO , the result is a clear solution and generates heat due to an

2 4

exothermic reaction. The addition of H SO aims to test the anion. When

2 4

concentrated sulfuric acid is poured over solid potassium bromide, a

reddish-brown solution is first formed, then reddish-brown bromine vapor

accompanies the released hydrogen bromide.

The reaction:

KBr + H SO HBr + HSO + K

2 4 4 - +

2KBr + 2H2SO4 2 4 2

_ Brother 2 + SO + SO 2- + 2K + +2H O

(Svehl, 1985) .

Then the 3rd Test, the addition of AgNO and HNO . The

3 3 was carried out

addition of AgNO aims to precipitate some silver anions which may

precipitate in the form of salts with Ag and HNO for a definitive test,

+ 3 cations

namely to strengthen the presence of silver ions in the sample in the

presence of HNO . The positive test when Br

3 precipitate - ions in the sample

solution was added with AgNO and HNO was a cloudy white solution and

3 3

there was a yellowish white precipitate. AgNO and HNO will precipitate

3 3

Br as AgBr. However, in this experiment the result was a clear solution and

no precipitate, which means that the KBr solution does not contain silver

anions.

The reaction:

KBr + KNO3 AgBr

AgNO3 +

Yellowish white precipitate

(Svehl, 1985) .

This precipitate can be formed because the product of the

concentrations of the ions involved is higher than the product of the

solubility of the solution, or it can be written Qc > Ksp. The Ksp of AgBr is

equal to 4 x 10 -13 (Svehl, 1985) .

The solution is said to be saturated when a precipitate forms. According to

the literature, when Br in KBr is reacted with AgNO3, produces a cloudy

solution and a white precipitate of AgBr is formed. After that, HNO3 was

added dissolve the AgBr precipitate. The result is that the solution obtained

is clearer than before but the precipitate is not soluble. This is because the

AgBr compound is stable and has a high density making it difficult to

dissolve with the addition of dilute . AgBr has a very small Ksp (4x10

HNO3 -13

) so it is insoluble with the addition of HNO3 has a low concentration.

which

So, in this test the addition of HNO aims to strengthen the identification

that the presence of Br forms AgBr precipitates that are insoluble with

- ions

dilute HNO . AgBr can dissolve in dilute ammonia which shows that the

sample contains Br . The test results were not in accordance with the

- ions

literature because the reagent that was dropped was contaminated so that no

precipitate formed.

The reaction:

AgBr + + H O + NO ( White precipitate )

(s) HNO3 AgBr 2 3 -

(Svehl, 1985) .

Then in the 4th test, Ba(C H

2 3 O 2 ) , the result was that both

2 was added

solutions remained clear, which means that the bromide ion in KBr does not

belong to the calcium barium group. The addition of Ba(C H O )

2 3 2 2 aims

to precipitate the calcium barium group anion. While the addition of HCl for

the definitive test of calcium barium group anion .

The reaction:

KBr + Ba(C H O ) → K(C H O ) + BaBr2 2 3 2 2 2 2 3 2

(Svehl, 1985) .

So the final result of this experiment is a negative result, which indicates

that Ba ions are not identified in solution.

6.3 Test for Iodine ion in Potassium iodide

This experiment aims to identify the presence of iodide anions in

known samples using liquid chemistry methods based on the differences in

ion behavior when reacted with certain reagents. This experiment was

carried out to identify the presence of I- ions in the sample solution using

several tests. The color of the sample solution is clear and after adding

sulfuric acid (H SO ) the resulting solution remains clear, a milky yellow

2 4

precipitate forms but the sample solution in the tube feels hot. This happens

because of an exothermic reaction where there is heat transfer from the

system, namely the sample solution to the environment, namely the test

tube. The formation of a milky yellow precipitate indicates that the sample

solution does not contain I- ions. Because according to the literature, if it

contains I- ions it will form a white precipitate. Then the third test was

added AgNO and HNO to become cloudy white. The function of adding

3 3

AgNO and HNO is to precipitate I as AgI, the reaction is:

3 3 -

(Svehla 1985c) .

In the third test, it showed that the sample solution contained I- ions

because even though no precipitate formed, the result was a cloudy white

solution, almost precipitating. This could be due to the addition of too little

reagent so that it does not precipitate completely. Then the fourth test is by

adding Ba(C2H3O2)2 and HCl. The result is a clear solution. This fourth

test shows a negative result because there is no change, which is likely to

contain very few iodide ions and the product of the ions has not exceeded

the Ksp so that the solution is not saturated and the final result is negative .

6.4 Test for Sulfite Ions in Sulfitic Acid

The aim of this test is to identify the presence of sulfite anions in

known samples by the liquid chemistry method based on the differences in

the behavior of the ions when reacted with certain reagents. At first the Na 2

SO was clear. Identification of SO ions in the sample solution

3 sample solution 3 2-

by adding H SO concentrated, the solution turns cloudy and hot due to the

2 4

exothermic reaction that occurs in the solution. Then, AgNO to the

3 was added

solution and HNO , the sample solution turned clear with a white

precipitate . This is not in accordance with the literature, because AgNO 3

and used to precipitate silver group cations (Svehla 1985b) . In the

HNO3

sample Na SO There are no silver group cations so no precipitate should

2 3

be produced. The next test is the addition of Ba(C H O ) and HCl in the

2 3 2 2

sample. The result is a cloudy white solution . The addition of HCl serves as

a catalyst that can accelerate the reaction, but can be reformed after the

reaction occurs. According to the literature, sample solutions containing

sulfite ions will produce a precipitate when tested by adding Ba(C H O )

2 3 2

2 , according to the following reaction:

Ba + SO BaSO

2+ 3 2- 3

(Svehla 1985b) .

3 precipitate can be formed because the product of the concentrations of Ba

2+ 2-

and SO 3 ions is greater than Ksp BaSO 3 . Price of Ksp BaSO 3 alone is

8×10 (Svehla 1985b) . I on SO should become supersaturated with the

-7 3 2-

addition of Ba(C H O ) and HCl s so that a white precipitate forms after

2 3 2 2

the addition of the two solutions. However, the results obtained in the

experiment were that the solution was only cloudy white. This indicates that

the solution is not saturated, so that precipitate does not arise. However,

with the appearance of a white precipitate, it shows results that almost form

a white precipitate, so it can be said that the result is positive. Ba 2+ ion

addition _ will precipitate calcium-barium anion groups, so the positive test

for SO 3 2 - ions is the formation of BaSO 3 precipitate (Svehla 1985b) .

6.5 Sulfate Ion Test in Sodium Sulfate

The aim of this experiment is to identify the presence of

sulfate anions in known samples using the liquid chemistry method based on

the differences in the behavior of the ions when reacted with certain

reagents . This experiment begins with the appearance of a

clear colored solution. Then do the addition of concentrated

H2SO4 . From this addition, the temperature of the solution

rises so that it is hot and the solution remains clear . The

addition of H SO aims to acidify the solution. After that,

2 4

AgNO and HNO were added . The function of adding AgNO

3 3

and HNO was to precipitate silver group anions and ensure

the presence of silver group anions in solution. The results

showed no change because there was no silver group anion,

the solution remained clear . However, on the addition of

AgNO a white precipitate was formed while on the addition

of HNO no precipitate occurs . Then add Ba(C H O )

3 2 3 2 2 and

HCl. Addition function Ba(C H O ) is to precipitate sulfate

2 3 2 2

and barium. On addition of Ba(C H O ) the solution

2 3 2 2 ,

becomes cloudy . While the function of adding HCl is for a

definitive test and to strengthen the identification that there is SO in the

4 2- ion

sample. The result is that the solution also remains cloudy but

there is a white precipitate which indicates a positive result

identified by sulfate ions.

The reaction that occurs:

Ba + SO BaSO (white precipitate)

2+ 4 2- 4

(Svehla 1985c) .

Based on the literature, after adding Ba(C H O ) be a white

2 3 2 2, there should

precipitate because the BaSO precipitate is formed because the product of

the concentrations of Ba and SO ions is greater than the Ksp of BaSO .

2+ 4 2- 4

The Ksp of BaSO is 1.1 x 10

4 -11 (Svehla 1985c) . The BaSO 4 solution is

supersaturated with the addition of Ba(C H O ) so that a precipitate

2 3 2 2

forms. The conclusion is that sulfate ions in Na SO

2 4 can produce precipitate when Ba(C

2 3 2 2

H O ) and HCl are added which shows a positive result because sulfate

ion (SO ) belongs to the calcium-barium group.

4 2-

6.6 Test for Phosphorus Ion in Phosphoric Acid

The purpose of this experiment is to identify phosphate ions in a solution of

H PO In this experiment, the first thing to do is to add a sample of a clear

3 4.

H PO SO ) which is obtained the solution

3 4 solution in a test tube and add sulfuric acid (H 2 4

remains clear, but the sample solution in the tube feels hot. This happens

because of an exothermic reaction where there is heat transfer from the

system, namely the sample solution to the environment, namely the test

tube. The next step was the addition of AgNO and HNO

3 3 to the sample

solution, and a clear solution was obtained but there was a yellow

precipitate. This does not indicate the presence of silver group ions in the

sample, because according to the literature, if silver group ions are

identified, a white precipitate will form. Then the sample solution was

added Ba(C H O ) and HCl, the result obtained was that the solution

2 3 2 2

turned cloudy and there was a white precipitate which showed a positive

result identifying sulfate ions.

The reaction that occurs:

3Ba + 2PO Ba (PO )

2+ 4 2- 3 4 2 (precipitate)

(Svehl, 1985) .

The precipitate Ba (PO )

3 4 2 is formed because the product of the concentrations of Ba 2+ and

PO ions is greater than Ksp Ba (PO ) where Ksp Ba (PO ) is 3.4 x

4 2- 3 4 , 3 4 2

10 (Svehla , 1985) .

-23

This is because the BaPO is supersaturated with the addition

4 solution

of Ba(C H O ) so that a precipitate forms. In conclusion, phosphate ions

2 3 2 2

in NaH PO Ba(C H O ) and HCl are added because

2 4 can produce precipitate when 2 3 2 2

phosphate ion (PO ) belongs to the calcium-barium group with a positive

4 3-

result, namely a white precipitate forms.

6 .7 Nitrate Ion Test in Lead(II) Nitrate

In this experiment, tests were carried out for nitrate ion in Pb(NO )

3 2

which aimed to identify the presence of nitrate anion in Pb( NO )

3 2 solution. This

experiment was carried out by placing 5 drops of 3 2

Pb( NO ) solution into a test tube. . After

observing the results obtained a yellow solution. Then added H2SO4 which

aims as a catalyst to accelerate the reaction. The result obtained is that the

solution remains yellow and hot due to an endothermic reaction that

produces heat. The reaction that will occur is as follows:

4NO + 2H SO ---- 4NO + O + 2SO

3 - 2 4 2 2 4 2- + 2H 2 O

(Svehla 1985d) .

After that, the next experiment was carried out by adding a nitrate

solution with 5 drops of into the test tube. The result obtained is a

AgNO3

yellow solution . Then the solution was added again with 5 drops of HNO3

and the result obtained was that the solution became clear. The addition of

HNO aims to identify the presence of anions in the sample . No precipitate

formed indicates a positive result.

Then an experiment was carried out by adding a solution of nitrate with

5 drops of Ba(C H O )

2 3 2 2 and the result obtained was that the solution

became cloudy. Then the solution was added again with 5 drops of HCl and

the result obtained was that the solution remained cloudy. In the literature it

is known that nitrate ions are dissolved ions which in this experiment should

not have formed a precipitate, so it can be seen that a positive result

indicates the presence of nitrate ions in solution.

6.8 Chromate Ion Test in Potassium Chromate

This experiment was carried out with the aim of identifying the

presence of CrO 4 2- in K CrO The work step is to put the K

ions 2 4 solution . 2

CrO in a test tube, the solution before being given the addition of a

4 solution

clear yellow reagent, after that the addition of H SO the result

2 4 is done,

obtained is that the solution changes color to orange and warm, this

indicates an exothermic reaction. occurs in solution . Then the addition of

AgNO3 was carried out precipitate the silver group anions, the results

obtained by the solution turned brick red, the reaction:

CrO + Ag Ag CrO

4 2- 2+ 2 4

(Svehla 1985a) .

This precipitate was formed because the Ag CrO

2 4 solution was

supersaturated with the addition of AgNO . In addition, because the

product of the concentrations of the ions is greater than Ksp Ag CrO

2 4

(Ksp Ag CrO = 2.4 x 10 ) (Svehla 1985c) . However, the results

2 4 -12

obtained do not contain precipitate, so the solution is said to be

unsaturated .

then added HNO3 clear yellow solution . the function of

to get a

adding HNO to ensure that the anions present in the sample and

precipitate are insoluble . Furthermore, Ba(C 2 H O ) was added to

3 2 2

precipitate the chromate from barium. The result obtained is that the

solution becomes brick red in color . Reaction :

CrO + Ba → BaCrO

4 2- 2+ 4

(Svehla 1985b) .

In the literature a positive result will form a precipitate. The

precipitate is formed because the solution is too saturated with the

substance in question and the product of the concentrations of the ions

has been exceeded, the price times the solubility or can be written

Qc>Ksp. After that, HCl was added for the definitive test and to confirm

the identification that there is a CrO in the sample. In addition, HCl

4 2- ion

aims to dissolve the precipitate. The result obtained is the solution turns

brick red . Reaction:

BaCrO + 2HCl → BaCl ↓ + H Cr O

4 2 2 2 4

(Svehla 1985d) .

The precipitate that is formed becomes soluble, this indicates a

reaction to HCl, because [BaCl] < [BaCrO ]. Therefore the sample

proved to be chromate ion of the potassium barium anion group which

showed a positive result .

6.9 Unknown solution test

An unknown solution is a solution whose anion content is unknown in

the solution, so we need to identify the solution from the results obtained

when testing it with several reagents, then identify and conclude the anion

content and adjust it to the literature.

In the 1st test, the appearance of the unknown solution is in the form of

a clear solution and when it is dripped with concentrated sulfuric acid there is

an increase in temperature, which means that the reaction that is taking place

is an exothermic reaction, because heat leaves the system to the surroundings.

The results of test-1 and test-2 are too general because most of the anions

give the same results. So it cannot be concluded that there are anions

contained. During the 3rd test with AgNO the results obtained are still

3 added

the same, it can be concluded that the anion is not from the silver group, then

when HNO however, the results show the same thing. However, when

3 is added

added with Barium oxalate, the solution became cloudy, and when HCl was

added the results showed a white precipitate and the solution became cloudy.

It can be concluded that the anions present in Unknwon's solution are anions

from the calcium-barium group, the anions in this group include SO , PO

4 3- 4

3- 2-

, CrO 4 , C 2 O 4 2- . Which is in accordance with the literature, namely the

calcium barium group anion will be precipitated by Ca or Ba

2+ 2+ (Svehla 1985a) .

VII. CLOSING

7.1 Conclusion

-Cl reacted with cloudy white AgNO + HNO , white precipitate

- solution 3 3 

-Br solution reacted with AgNO + HNO clear solution , no precipitate

- 3 3 

-Solution I reacted with AgNO + HNO cloudy white solution

- 3 3 

-SO and SO reacted with Ba (C H O ) clear solution of white

3 - 4 2- solutions 2 2 2 2 

precipitate in SO solution and cloudy solution has no precipitate in SO

3 - 4 2-

solution

-CrO 4 2- solution reacted with Ba (C 2 2 2 2

H O ) + OH brick red solution

-

-PO solution reacted with Ba (C H O )

4 3- 2 2 2 2 + HCl cloudy solution and

there was a white precipitate

-NO reacted with concentrated H SO plus Ba (C H O )

3 solution - 2 4 2 2 2 2 cloudy

solution

-Unknown solution formed a cloudy solution and there was a white

precipitate and it was identified as belonging to the calcium-barium group.

7.2 Suggestion

- It is better to use reagents that are still in good condition to get good results

- Systematic addition of reagents according to the instructions in the

practicum manual

- Observe the changes that occur carefully with each addition of the reagent

BIBLIOGRAPHY A

Basri, Sarjoni. 1996. . Jakarta: Rineka Cipta.Chemistry Dictionary

———. 2000. . Jakarta: Rineka Cipta.Chemistry Dictionary

Chang, DY 1996. "Application of the Extent Analysis Method on Fuzzy AHP."

European Journal of Operations Research 95: 649–55.

Chang, Raymond. 2004. Basic Chemistry: Core Concepts . third. Jakarta:

Erlangga.

Daintith, John. 1994. . Jakarta: Erlangga.Complete Dictionary of Chemistry

Harjadi, W. 1990. Basic Analytical Chemistry . Jakarta: Gramedia Publisher.

Sixth, Charles. W. 1992. . Jakarta: Erlangga.Chemistry for Universities

Svehla. 1985a. Textbook of Macro and Semimicro Qualitative Organic Analysis .

Jakarta: PT Kalman Media Pustaka.

Svehla, G. 1985b. Macro and Semimicro Inorganic Analysis . Jakarta: PT Kalman

Media Pustaka.

Svehla, G. 1985c. “Macro And Semimicro Qualitative Inorganic Analysis.” Fifth

edition, part I. Jakarta: Kalman Media Pustaka .

1985d. Textbook of Macro and Semimicro Qualitative Organic Analysis . Jakarta:

PT Kalman Media Pustaka.

Shukri. 1999. . II. Bandung: UI Press.Basic Chemistry

Attachment

1. Chloride ion test

Test 1 Test 2 ( concentrated H SO ) Test 3

2 4

(AgNO )

Test 3 (HNO ) Test 4 ( Ba(C H O ) ) Test 4 (HCl)

3 2 3 2 2

2. Bromide ion test

Ba(C H O ) addition solution

2 3 2 2

3. Iodine Solution Test

Tests 1 and 2 Tests 3(AgNO ) Tests 3 (HNO )

3 3

Test 4 ( Ba(C H O ) ) Test 4 (HCl)

2 3 2 2

4.Sulfite Ion Test

Tests 1 and 2 Test 3 (AgNO ) Test 3 (HNO )

3 3

Test 4 ( Ba(C H O ) ) Test 4 (HCl)

2 3 2 2

5.Sulfate Ion Test

Tests 1 and 2 Test 3 (AgNO ) Test 3 (HNO )

3 3

Test 4 ( Ba(C H O ) ) Test 4 (HCl)

2 3 2 2

6. Test Phosphate Ions

Test 2

Test 3

(Appearance) (H2SO4)(AgNO3)

Test 4

(HNO3) ( Ba(C H O )

2 3 2 2 HCl

7 . Nitra test t

Test 1 Test 2 Test 5

Appearance of Solution Addition of H SO Nitrate Test

2 4

Test 3 Test 3 Test 4

Addition of The addition of HNO3

AgNO3 Addition

( Ba(C H O )

2 3 2 2

Test 4

8. Chromate Test

Chromate ion

solution + _ +AgNO

H2SO4 _ 3

Ba + HCl

9. Unknown solution test

Test 1 Test 2 Test 3

(Appearance) (H2SO4)(AgNO3)

Test 3 Test 4 Test 4

(AgNO3) ( Ba(C H O )

2 3 2 2 HCl

CHEM 302 LIBERTY UNIVERSITY Report P2 Organic Sulfide_SUMMARIES_2023.pdf

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