Chemistry

The p-Block Elements.

Question:

What happens when sulp'hur dioxide is passed through an aqueous solution of Fe(III) salt?

Answer:

SO2 acts as a reducing agent and reduces aqueous solution of Fe (III)salt to Fe (II) salt.
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The p-Block Elements.

Q 1.

Write the reactions of F2 and Cl2 with water.

Q 2.

Match the formulas of oxides given in Column I with the type of oxide given in Column II and mark the correct option.
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Q 3.

 Write the order of thermal stability of the – hydrides of Group 16 elements.

Q 4.

Can PCl5 act as an oxidising as well as a reducing agent Justify.

Q 5.

Why are halogens coloured?

Q 6.

Match the compounds given in Column I with the hybridization and shape given in Column II and mark the correct option.
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Q 7.

 Write two uses of ClO2

Q 8.

 Write balanced equations for the following:
(i) NaCl is heated witlrsulphuric acid in the presence of MnO2
(ii) Chlorine gas is passed into a solution of Nal in water.

Q 9.

Write a balanced equation for the hydrolytic reaction of PC is in heavy water.

Q 10.

How is the presence of SO2 detected ?

Q 11.

Give the resonating structures of N02 and N2O5.

Q 12.

Write two uses of ClO2

Q 13.

What are the oxidation states of phosphorus in  the following: –
(i) H3PO3 (ii)PCl3
(iii) Ca3P2(iv)Na3PO4
(v) POF3

Q 14.

Write a balanced chemical equation, for the reaction showing catalytic oxidation of NH3 by atmospheric oxygen.

Q 15.

 Why is BiH3 the strongest reducing agent amongst all the hydrides of group 15 elements? (C.B.S.E. 2013)

Q 16.

What happens when sulp’hur dioxide is passed through an aqueous solution of Fe(III) salt?

Q 17.

Write the conditions to maximise the yield of H2SO4 by Contact process.

Q 18.

 Why does nitrogen show catenation properties less than phosphorus ? (C.B.S.E. Foreign 2009)

Q 19.

Why is dioxygen a gas but sulphur a solid?

Q 20.

Which one of the following does not exist ?
(i)XeOF4 (ii)NeF2
(iii)XeF4 (iv)XeF6

Q 21.

List the uses of neoirand argon gases.

Q 22.

Reduction potentials of some ions are given below. Arrange them in decreasing order of oxidizing power.
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Q 23.

Which of the following orders are correct as per the properties mentioned against each?
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Q 24.

Give reason to explain why ClF3 exists but FCl3 does not exist.

Q 25.

 How is nitrogen prepared in the laboratory? Write the chemical equations of the reactions . involved.

Q 26.

Why is BiH3 the strongest reducing agent amongst all the hydrides of Group 15 elements?

Q 27.

Why is N2 less reactive at room temperature?

Q 28.

List the important sources of sulphur.

Q 29.

Write the order of thermal stability of the – hydrides of Group 16 elements.

Q 30.

Which of the following does not react with oxygen directly?  Zn, Ti, Pt, Fe

Q 31.

How is O3 estimated quantitatively?

Q 32.

Comment on the nature of two S-O bonds formed in S02 molecule. Are the two S-O bonds in this molecule equal ?

Q 33.

Mention three areas in which H2SO4 plays an important role.

Q 34.

Why does NH3 form hydrogen bond but PH3 does not?

Q 35.

Explain why NH3 is basic while BiH3 is only feebly basic.

Q 36.

Nitrogen exists as diatomic molecule and phosphorus as P4. Why?

Q 37.

Why are halogens strong oxidising agents?

Q 38.

Explain why fluorine forms only one oxoacid, HOF.

Q 39.

Write the reactions of F2 and Cl2 with water.

Q 40.

What inspired N. Bartlett for carrying out reaction between Xe and PtF6?

Q 41.

With what neutral molecule is CIO isoelectronic? Is that molecule a Lewis base?

Q 42.

How are XeO3  and XeOF4prepared?

Q 43.

Give the formula and describe the structure of a noble gas species which is isostructural with:  (i) ICI4 (ii) IBr2 (iii) Br03

Q 44.

Why do noble gases have comparatively large atomic sizes?

Q 45.

On addition of cone. H2SO4 to a chloride salt, colourless fumes are evolved but in case of iodide salt, violet fumes come out. This is because
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Q 46.

In qualitative analysis when H2S is passed through an aqueous solution of salt acidified with dil. HCl, a black precipitate is obtained. On boiling the precipitate with dil. HNO3, it forms a solution of blue colour. Addition of excess of aqueous solution of ammonia to this solution gives
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Q 47.

Which of the following pairs of ions are isoelectronic and isostructural?
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Q 48.

A brown ring is formed in the ring test for NO3 ion. It is due to the formation of
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Q 49.

In PCl5, phosphorus is in sp3d hybridised state but all its five bonds are not equivalent. Justify your answer with reason.

Q 50.

SF6 is known but SCl6 is not. Why?