The individual dihydroxybenzene solutions are mixed with aqueous FeCl₃. 4 mL of FeCl₃ solution are poured into the first conical measure, 10 mL into the second measure and 20 mL into the third measure.
Results:
When treated with aqueous FeCl₃, the aqueous dihydroxybenzene solutions will show the characteristic color change.

Discussion:

Like phenol also catechol and resorcinol do form a colored complex with FeCl₃.

Hydroquinone is oxidized rapidly to p-benzoquinone, which does not generate a colored complex with FeCl₃.

Redox equilibrium between hydroquinone and p-benzoquinone:

Resorcinol shows no redox reaction with Fe³⁺. The two hydroxy groups in the meta position can not form a quinoid system. Thus a redox reaction between resorcinol and Fe³⁺ is impeded.

Catechol is only partially oxidized to o-benzoquinone.

Results:

Discussion:

· Diazotized sulfanilic acid (1) reacts with phenol and the naphtholes forming acid azo dyes (2) The reaction proceeds according to the mechanism of electrophilic aromatic substitution.

When a-methyl carbonyl compounds react with iodine in the presence of a base, the hydrogen atoms on the carbon adjacent to the carbonyl group (a hydrogens) are subsituted by iodine to form tri iodo methyl carbonyl compounds which react with OH - to produce iodoform and carboxylic acid (2):

Reaction mechanism:

The hydrogen atoms on the methyl group are slightly acidic and can be removed with hydroxide. The carbanion formed then react with iodine molecules to give a iodide ion and a monoiodonated methyl carbonyl derivate. Introduction of the first iodine atom (owing to its electronegativity) makes the remaining hydrogens of the methyl group more acidic. Hence a base-catalized iodination of a monohalogenated methyl carbonyl derivate occurs at the carbon that is already substituted. Finally a tri iodo methyl carbonyl derivate is formed.

The next step is a nucleophilic attack by hydroxide on the carbonyl carbon atom. A carbon-carbon bond cleavage occurs and a triiodomethanide ion departs. The triiodomethanide ion is unusually stable. Its negative charge is dispersed by the three negative iodine atoms. In the last step a proton transfer takes place between carboxylic acid and triiodomethanide ion to form ultimately carboxylate ion and iodoform.

Chemicals:
cyclohexene
benzene
₁₀-2 M aqueous bromine (1.28 g bromine / 800 mL H2O)
₁₀-4 M aqueous KMnO4 (12.6 mg KMnO4 / 800 mL H2O)
Apparatus and glass wares:
4 graduated cylinders with stopper 500 mL
2 pipettes 1 mL, graduated in 0.1 mL
2 pipet bulbs
4 snap-cap vials 10 mL
Experimental procedure:
Two snap-cap vials contain 0.75 mL benzene. 0.8 mL cyclohexene are pipetted into each of two further snap-cap vials. Two collecting cylinders are each filled with 10-2 M aqueous bromine and two further cylinders are filled with 10-4 M aqueous KMnO4. The solutions are mixed with benzene and cyclohexene, respectively
The stoppered cylinders are vigorously shaken.
Results:
Benzene reacts neither with aqueous bromine nor with permanganate solution. Cyclohexene reacts with both aqueous bromine and permanganate. The solution of bromine is decolorized and purple permanganate turns brown.
Discussion:
The decolorization of bromine water is often used as a test for a carbon-carbon double bond. Bromine undergoes electrophilic addition to the double bond of alkenes. In non-aqueous solvents such as carbon tetrachloride, this gives the di-bromo product. For example, reaction with ethylene will produce 1,2-dibromoethane. When used as bromine water, the corresponding bromohydrin is formed instead.

On approaching the electron dense area of the p bond of cyclohexene, the bromine molecule becomes polarized. The electron density of the bromine is shifted, so that one bromine is partially positive and the other is partially negative charged. The Br-Br bond is heterolytically cleaved. The positively charged bromine atom acts as an electrophile, reacting with the C=C double bond. A cyclic bromonium ion is formed. The subsequent attack of the bromide ion on the three-membered ring can proceed only from the back-side, because the front-side attack is sterically hindered. The result is formation of a mixture of two enantiomeric compounds of trans-1,2-dibromocyclohexane. (1). When other nucleophiles such as water or alcohol are existing, these may attack the cyclic bromonium ion to give an alcohol or an ether (2).

Also the permanganate hydroxylation is used as a qualitative test for the presence of an alkene (Bayer test). Permanganate converts cyclohexene into a diol. In the course of the reaction purple permanganate is reduced to brown manganese dioxide (3).

Since a syn-hydroxylation takes place, the reaction is thought to involve the formation of an intermediate cyclic hypomanganate ester which is readily hydrolyzed under the reaction conditions to yield the glycol (4). Experiments with 18O-labelled permanganate demonstrate, that the two oxygen atoms of glycol originate on the permanganate and not on the solvent.

Apparatus and glass wares:
3 graduated cylinder with stopper 500 mL
beaker 200 mL
Erlenmeyer flask with stopper 250 mL
temperature probe
temperature measuring device

Experimental procedure:
Using an Erlenmeyer flask with stopper, 108 g of sodium disulfite are dissolved in 200 mL of dist. water. Sodium disulfite dissolves in water to form bisulfite ions. The solution of disulfite is poured into a graduated cylinder containing 116 mL of benzaldehyde. The stoppered cylinder is shaken vigorously. After removing the stopper a temperature probe connected to a temperature measuring device is inserted into the reaction mixture.
Results:

In general, aldehydes are more reactive than ketones. There is a combination of steric hindrance and inductive effects that makes ketones to react slower than aldehydes (2).

- Bulky alkyl groups sterically hinder the approach of nucleophile.
-The electronic effects of alkyl substituents are weakly electron donating. So they make the C atom in carbonyl less electrophilic

The addition of bisulfite is usually employed to purify aldehydes. Aldehydes are isolated from reaction mixtures through its bisulfite derivatives. The addition compound can be split easily to regenerate the aldehyde by treating it with either dilute mineral acid or dilute alkali.

Combustion Engineering
Summary :
a-Combustion :
For the combustion of 1Kg fuel a certain amount of oxygen is required .
b-Kiln gas :
The kiln gas consists of :
1-Combustion products .
2-Excess air of combustion .
3-False air .
4-Gas from raw meal .
c-Analysis of kiln gases :
The orsat-analysis is used to analyze the dry kiln gases , from orsat-analysis we get :
1-Excess air factor ( n ) .
2-Incomplete combustion .
3-Heat consumption .
4-False air .
Combustion
A-Fuel :
We have three types of fuels :
a-Gaseous fuels .
b-Liquid fuels .
c-Solid fuels .
The combustible elements that characterize fuels are carbon , hydrogen and sulfer .The complete combustion of carbon gives carbon dioxide and hydrogen gives water .The products of complete combustion of fuel are CO2 ,H2O ,N2 and O2 .The presence of CO indicates incomplete combustion .
B- Heat of combustion :
Chemical change is accompanied by absorption of heat .Heat values that generated when 1Kg of fuel is completely burned .
Purpose Of The Gas Analysis
The knowledge of the gas composition in a cement plant is important to control the firing of kiln .The following points can be determined :
1-How complete the combustion of fuel .
2-How much excess air .
3-False air .
4-Specific consumption .

Portland Cement Clinker
1 – Clinker Mineralogy .
a – The phases which should theoretically be present in a cooled clinker of this composition .
b – The quantity of each phase which should be present :
I – C3S
II – C2S
III – C3A
IV – C4AF
Phase diagram CaO-SiO2-Al2O3 .
Phase diagram CaO-SiO2-Al2O3-Fe2O3
2 – Real Clinker Minerals .
What are the real chemical compositions of the clinker minerals ?
Pure compounds C3S , C2S , C3A not occur in this simple form , but contain oxides such as MgO , Na2O , K2O , Fe2O3 and Al2O3 .
Using analytical techniques :
a – Electron microprobe analyzer .
b – Energy dispersive analyzer .
Polymorphic modification of clinker minerals
We find that not only chemical composition vary clinker minerals , but some clinker phase also exist in different polymorphic forms , which can exhibit different physical properties .
a - C3S alite
Have 6 polymorphic modification between room temperature and 11000C . The changing appear in the lattice structure .
b - C2S belite ( β-C2S ) .
Have 5 modifications between room temperature and 15000C (γ , β ,α) . The change β to γ and γ to α are irreversible and slow .
c - C3A .
C3A present as a cubic lattice , but Na2O are incorporated within the lattice forming orthorhombic , monoclinic and tetragonal modification but they differ in their reactivates .
d - C4AF .
Pure C4AF is not found .
Quantitative clinker mineralogy
A – Calculation of potential clinker composition . By Bogue , which consider chemical equilibrium has been attained .
1 – Fe2O3+Al2O3+CaO= C4AF
2 - Al2O3+CaO= C3A
3 – SO3+CaO=CaSO4
4 – CaO+SiO2= C2S
5 - C2S+CaO= C3S
6 – MgO free .
# C3S=4.07*CaO-7.6*SiO2-6.72*Al2O3-1.43*Fe2O3-2.85*SO3

#C2S=2.87*SiO2-.754*C3S