1.
pH of an aqueous solution at 400°C is 6.76.

What is the nature of the solution

(acidic/basic/neutral) {Given Kw at 400°C is
2·92x Justify your answer,



What are the alkaline error and the acid error
of a glass membrane pH eloetrode7



W hat is solid phase extraction Write down

the main principle involved in it.


Silver forms ccp lattice and X-ray studies of

its crystals show that the edge length of its

unit cell is 408·6 pm. Calculate the density of

silver (Atomic mass 107.9U



State the purpose of an auxiliary complexing
agent and taking an example, illustrate its use.



20 ml of an aqueous solution of 0.10 M butyric

acid was shaken with 10 ml ether. After the layerS

were separated, it was determined by

titration that 0·5 mol of butyric acid remained

remained in the aqueous layer. W hat is the

distribution ratio and the per cent extracted




Ni in steel to be analyzed from 1.0 g or

steel sample. What volume of wt of DMG

(dim ethyl glyoxime) in alcohol to be used

to provide a 50% excess of DMG for the

analysis. The density or alcohol (0·79 g/ml).

FM Ni(58·69); DMG( 116·12).



Write down the principles of High Performance

Liquid Chromatography (HPLC) and Gas Liquid

Chromatography (GLC).


In atomic absorption spectroscopy what

is the significance of background absorption

and background correction.



Given,

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2. 25-00 ml liquid bleach was diluted to 1000 ml

in a volumetric Flask, An aliquot of 25 ml of

this diluted sample was transferred to an

Erlenmeyer flask and treated with excess Kl.

This gets oxidized to Kl, and the bleach OCL- to

Cl-. The liberated I2, in the form or KI3,

required 8·96 ml of 0.09892 M Na2S203, to

titrate using starch as indicator. Find out the

WN NaOCI in the bleach sample.



Lay down the procedure to separate and then

estimate the constituents Cu, Zn, Sn. Pb and

Fe of the Brass alloy.




Consider a mixture of the two solids

BaCl2.2H20 M 244.26) and KC1 (FM

74·55). When 1he mixture is healed at 160°C

for 1h the water of crystallization is driven

off. A sample originally weighing 1.783 g

weighed 1.5623 g after heating. Calculate the

weight of Ba, K and Cl in the original

sample.

3. The amount of Fe in a 0-4891 g sample of

an ore was determined by a redox titration

with K2Cr2O7• The sample was dissolved in

HCl and the iron brought in t0 oxidation

state using Jones reductor, Titration using

diphenylamine sulfonic acid as indicator, the

end point required 36·92 ml of 0·02153 M of

K2Cr2O7. Report the iron content of the ore as

Fe203.

Fill in the blanks

When you double the frequency of electromagnetic

radiation. you the energy.


When you double the wavelength, you

the energy.

When you double the wave number, you

the energy.

10% transmittance equals

absorbance.

When you double the path length, you

absorbance,









Write down the equations in terms of the acid

dissociation constants and for the highest

alpha value for each of the following

Tartrate

Acetate

Phosphate

Nitrilo ace-lie acid

EDTA

4.
Calculate the H3O+ (hydronium ion) concentration

for a buffer solution of 2 M phosphonic

acid and l.5 M potassium hydrogen phosphate

(Ka1=7·11x10^-3; Ka2 6·32•10^8].

How many milligrams of CO2, and H,O will be

produced from the combustion of 4·635 mg of

benzoic acid


Define acid-base indicator. Suggest the

transition pH -range with colour changes in

methyl orange and phenolphthalein indicators.



5.
A solution of carbon in face centered cubic

iron has a density of 8.105 g and a unit

cell edge of 3.589 A. Are the carbon atoms

interstitial or do they substitute for iron atoms

carbon.



A brown ore confuged as red hematite or

pyrolusite requires different tarif rates for

transport. As analyst, you performed a fusion

test of the ore using Na2C03-Na202. You

leached the mass once get cooled with

water. The leached colour would either be

brow n-violet or green in colour. On acidification

with cold dilute H2SO4, the colour

vanishes quickly or acquired a violet colour.

Based on the observations, can you identify

the brown ore. Explain the expected changes

in colour if the ore was for an iron or for a
manganese.



Sketch photometric titration curves for the
following conditions:
following conditions

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6.
In a UV-visible spectrum, if you observe a

negative absorbance, suggest the reasons that

can be responsible for 1his and possible

can be responsible for this and possible

remedies.

Plot a measured value of pipet against the

percentage of measurements in an experiment

to plot a histogram showing the distribution of

say 50 results. Correlate this his1ogram with a

Gaussian Curve bearing same mean and

standard deviation.
in range 14, 18, 26, 14, 10,

No. in range: 13,


1.022 g of KI03 (FM 214) was dissolved and

dissolved and made up to 500 ml in a standard

measuring flask. when 50 ml of this solution was

treated with excess KI and a mineral acid

(10ml of0·5 ¡3- are produced. Find out the

moles of 13.


7. Answer all of the following:


Arrange the following compounds in the order

of decreasing acidity. Explain your answer.

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Predict the product of the following reaction

and write the mechanism involved. and write the

mechanism involved.

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Complete the following reaction and propose a
suitable mechanism for it.

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Which of the following compounds A and

has the greeter dipole moment? Explain.

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Complete the following reaction and propose a

suitable mechanism.

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Sketch the following π-molecular orbitals

showing nodes

HOMO for 3-butadiene


LUMO for ally cation


Explain why the compound A exists exclusively in

the enol form and the compound B

exists exclusively in the keto form.

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Write the major product(s) of the following
reaction sequence.


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Arrange the compounds B and C in the

order decreasing stretching frequency of 0

in the IR spectrum. Justify your arrangements.

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The mass spectrum of an unknown compound

has a molecular ion peak with a relative

intensity of 43.27% and an M l peak with a

relative intensity of 3.81%. How many carbon

atoms are present in the compound



8. Classify the following com pounds into

aromatic, antiaromatic and non-aromatic.

Explain your answer.



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Arrange the following Carbanions in their

decreasing order of stability. Give reasons for

the order given by you.


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Describe Heinsberg's method of separation of

amines.



9. Give the main product of the following reactions

and give plausible mechanisms involved for its

formation.


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10.predict the major product(s) in the following

"eactions. Suggest a suitable mechanism involved

in each case.

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11 .
The cyclic compound A exhibits enhanced

acidity when compared to acyclic compound B.

Rationalize the observation.


What are ylides How the stabilized and

unstabilized phosphorus ylides yield different

products in the Wittig reaction with a cyclic

ketone.







Benzoin condensation fails or gives very low

yields if the aldehyde contains e l S r o n

donating or electron withdrawing groups.

Explain.


12. Why do polar solvents shift the

transition to a longer wavelength and n

transition to a shorter wavelength .

A non-polar organic compound with molecular

formula C4H60 does not show any significant

UV absorption and has IR absorption at

3300-2900 and 2200 Its M R spectrum

consists of three singlets at δ 3.0

3·5 and 4·9 Elucidate the structure

of the compound.



An organic compound with molecular formula

C8H803 gives the following spectral data.

Assign a suitable structure to the compound,

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