•Properties of Sulfuric acid1.Physical2.Chemical

1.Standard Reactions3.Structural

•Manufacturing Process•Industrial and Laboratory Usage•Environmental and Health Issues

•Chemical Formula: H2SO4•Appearance: Transparent [colourless]•Texture: Oily•Molar Mass: 98.078g/mol•Boiling Point: 315-338°C•Melting Point: 10.35°C•Density: 1.84g/cc [25°C]•Heat Capacity: 1.414J/Kg

•Acidity: -3 pH•Acid Type: Diprotic•Corrosiveness: Very High•Reactivity: High•Solubility: Miscible•Oxidizing Power: High•Volatility: Low

Metal Sulfuricacid Metalsulfate Hydrogen

Hot concentratedMetal Sulfuricacid Metalsulfate ulfur dioxide WaterS

2 3 2 4 2 4 2 2

Metalcarbonate Sulfuricacid Metalsulfate Carbon dioxide water

x xX CO xH SO X SO xCO xH O

2 4 2 4 2

Base SulfuricAcid MetalSalt Water

2 2x x

X OH xH SO X SO xH O

3 2 4 4 42

Ammonia Sulfuricacid Ammoniumsulfate

2NH H SO NH SO

H O

O

SO

O

H

The Contact Process

Combustion

Chamber

PurifierElectrosta

tic Precipitat

or

Conversion

ChamberT = 450°C

P = 1-2atmV2O5

Absorption Towers

Wet Sulfuric Acid

Hydration of

Disulfuric Acid

H2SO4

( )sS

2( )gO

Recycling of Unreacted Material

2( )gSO3( )gSO

[98%]

2( )gSO

[Impurities]

( ) 2( ) 2( )g g gS O SO

3( )gSO

2 4( )aqH SO

3( ) 2 ( ) 2 4( )g l lSO H O H SO

3( ) 2 4( ) 2 2 7( )g aq aqSO H SO H S O

2 2 7( )aqH S O

2 2 7( ) 2 ( ) 2 4( )aq l aqH S O H O H SO

The Contact Process

Step by step of contact process

1.Combustion of sulfur to sulfur dioxide2. Oxidation of sulfur dioxide to sulfur trioxide3. Reaction of sulfur trioxide and sulfuric acid 4.Hydration of disulfuric acid yielding sulfuric acid as product

Equations of contact process

1.S(s) + O2(g) SO2(g)

2.2SO2(g) + O2(g) 2SO3(g) [Done via a vanadium oxide catalyst – V2O5]

3.(a) SO3(g) + H2O(l) H2SO4 (aq) [WSAP]

(b) SO3(g) + H2SO4 (aq) H2S2O7 (aq) [DCDA]

4. H2S2O7 (aq) + H2O(l) 2H2SO4 (aq)

An electrochemical cell capable of a reverse reaction.

Sulfuric acid is used as the electrolyte solution

Cathode reaction:PbO2 (s) +4H+ (aq) + 2e-

Pb2+ +2H2O (l)Anode reaction:Pb (s) Pb2+ (aq) +2e-

[1]

[2]

[1} - http://upload.wikimedia.org/wikipedia/en/6/64/Lead-acid_discharging.svg[2] - http://upload.wikimedia.org/wikipedia/en/1/1c/Lead-acid_charging.svg

English land-owner John Lawes discovered in 1842 a technique to produce a superphosphate.

Supplies soil with the required nutrients for healthy growth

Pickling is the treatment of metallic surfaces to remove impurities, stains and rust via a solution.

The surface is dipped in a solution known as a pickle liquor which is usually an acid.

Two most commonly used acids are sulfuric and hydrochloric.

Due to the pickle liquors corrosive properties, ‘hydrogen embrittlement’ can occur.

Hydrogen from the acid reacts with the metal surface causing cracks and thus an overall loss in strength.

[1]

The drying capability of sulfuric acid enables it to char organic molecules; as water is extracted.

This effect can be observed when concentrated sulfuric acid is added to sucrose.

Since sucrose is a carbohydrate, when the water is extracted we are left with elemental carbon

C11H22O12 (s) + 11H2SO4 (aq) 12C(s) + 11[H2SO4 . H2O]

[1] – Slater B, The chemistry dimension

Due to sulfuric acids low volatility it can be used in the manufacture of other acids such as HCl, HF, HNO3.

The general equation is shown below.

2XyYx + xyH2SO4 2xHyY + yX2 [SO4]x

Where:XyYx = Salt

X = Metal componentY = Non – metal componentx,y = valence of x and y respectively

This is not the case for the preparation of some acids, as the reactions will only proceed at high temperatures [550-600]o

The second equation is for salts that have a high reaction rate.

  XyYx +xyH2SO4 xHyY + yX

[H2SO4]x

Due to its dehydrating ability, contact with the skin will result in third degree burns.

Occurs because the reaction is exothermic, as the amount of water drawn from the skin increases, the intensity also increases

Sulfuric acid produced in the earths atmosphere is transferred to Earth most commonly as precipitation called ‘acid rain’.

Generally has a pH between 4.3 -5.0.

Caused mainly by industrial emissions such as combustion of fossil fuels causing particular emissions of SO2 and NOx

Decaying vegetation and erupting volcanoes contribute up to 20% of the emissions of SO2 and NOx