Which of the following on heating does not give nitrogen gas?

The element which forms oxides in all oxidation states +I to +V is

Which of the following compounds exists?

The formation of O₂⁺[PtF₆]^- is the basis for the formation of xenon fluorides. This is because

The orange solid on heating gives a colourless gas and a green solid which cab be reduced to metal by aluminum powder.  The orange and the green solids are, respectively,

The shape of O₂F₂ is similar to that of

Which one of the following reactions of xenon compounds are not feasible ?

Which of the following ion is colourless in aqueous solution ?

Identify the incorrect statement among the following :

Which of the following configuration of ions has zero CFSE in both strong and weak ligand fields? 

Draw the structural formulae of the following compounds:  (i) H₄P₂O_s  (ii) X_eF₄

Describe the manufacture of H₂SO₄ by contact process.

Write the conditions to maximise the yield of sulphuric acid by Contact process.

Assign a reason for each of the following:
(i) In group 15 the bond angle H-M-H decreases in the following order NH₃ (107.8^o), PH₃ (93.6^o), AsH₃ (91.8^o).
(ii) Sulphur hexafluoride is used as a gaseous electrical insulator.

Complete the following chemical reaction equations:
(i) Xe(g) + F₂(g)\(\underset { (in\ excess) }{ F_{2}(g) } \) \(\xrightarrow [7 bar]{873\ K}\)
(ii) Li + N₂  \(\rightarrow\)

Assign a reason for each of the following statements:
(i) The bond angle H-M-H in the trihydrides of Group 15 elements decreases from NH₃ downward.
(ii) SiF₆^2- is known but SiCI₆^2- is not known.

Give the resonating structures of NO₂ and N₂O₅.

The HNH angle value is higher than HPH, HAsH and HSbH angles.  Why?
[Hint: Can be explained on the basis of sp³ hybridisation in NH₃ and only s-p bonding between hydrogen and other elements of the group]

Magnetic moment of [MnCl₄]^2- is 5.92 BM. Explain giving reason.

Write the name, the state of hybridization, the shape and the magnetic behaviour of the following complexes:
[Ni(CN)₄]^2-, [CoCl₄]^2-,[Cr(H₂O)₂(C₂O₄)₂]^- (At. No: Co = 27, Ni = 28, Cr = 24)

Give the formula of each of the following coordination entities:
(i) Co³⁺ ion is bound to one Cl^-, one NH₃ molecule (en) molecules.
(ii) Ni²⁺ ion is bound to two water molecules and two oxalate ions.
Write the name and magnetic behaviour of each of the above coordination entities.
(At. nos. Co = 27, Ni = 28)

(a) Draw the structures of the following molecules:
(i) (HPO₃)₃
(ii) BrF₃
(b) Complete the following chemical equations:
(i) HgCl₂ + PH₃ \(\rightarrow\)
(ii) SO₃ + H₂SO₄ \(\rightarrow\)
(iii) XeF₄ + H₂O \(\rightarrow\)

(a) What happens when
(i) chlorine gas is passed through a hot concentrated solution of NaOH
(ii) sulphur dioxide gas is passed through an aqueous solution of a Fe (III) salt?
(b) Answer the following:
(i) What is the basicity of H₃PO₃ and why?
(ii) Why does fluorine not play the role of a central atom in interhalogen compounds?
(iii) Why do nobel gases have very low boiling points?

(a) Draw the structures of the following molecules:
\((i){ N }_{ 2 }O_{ 5 }\ (ii)\ HCIO_{ 4 }\)
(b) Explain the following of the molecular molecules:
(i) \({ H }_{ 2 }S\)is more acidic than
(ii) Fluorine does not exhibit any positive oxidation state.
(iii) Helium forms no real chemical compound

(a) Give reasons for the following:
(i) Bond enthalpy of \({ F }_{ 2 }\) is lower than that of  \(CI_{ 2 }\)
(ii)\(PH_{ 3 }\) has lower boiling point than
(b) Draw the structure of the following molecules: 
\((i)BrF_{ 3 }\quad (ii)(HPO_{ 3 })_{ 3 }\quad (iii)XeF_{ 4 }\quad \)

\(\)

(a) Complete the following chemical equations:
(i) \(NaOH+C1_{ 2 }\rightarrow \)
(hot and conc.)
(ii) \(XeF_{ 4 }+O_{ 2 }F_{ 2 }\rightarrow \)
(b) Draw the structurs of the following molecules:
(i) H₃PO₂
(ii) H₂S₂O₇
(iii) XeOF₄

Calculate the number of unpaired electrons in following gaseous ions: Mn³⁺, Cr³⁺, V³⁺ and Ti³⁺. Which one of these is the most stable in aqueous solution?

(a) Give the preparation of potassium dichromate from chromate ore:
(b) Explain the following:
(i) Transition metals have good tendency to form complexes.
(ii) Transition metals exhibit variable oxidation states.
(c) Write the general electronic configuration of lanthanoids.

Account for the following :
(a) Transition metals show variable oxidation states.
(b) Zn, Cd and Hg are soft metals
(c) E^o value for the Mn³⁺ /Mn²⁺ couple is highly positive (+ 1.57 V) as compared to Cr³⁺ /Cr²⁺.
(ii) Write one similarity and one difference between the chemistry of lanthanoid and actinoid elements.

On heating lead (II) nitrate gives a brown gas "A".  The gas "A" on cooling changes to colourless solid "B".  Solid "B" on heating with NO changes to a blue solid 'C'.  Identify 'A', 'B' and 'C' and also write reactions involved and draw the structures of 'B' and 'C'.