On addition of conc. H2SO4 to a chloride salt, colourless fumes are evolvedbut in case of iodide salt, violet fumes come out. This is because

(i) H2SO4reduces HI to I2

(ii) HI is of violet colour

(iii) HI gets oxidised to I2

(iv) HI changes to HIO3

In qualitative analysis when H2S is passed through an aqueous solution ofsalt acidified with dil. HCl, a black precipitate is obtained. On boiling theprecipitate with dil. HNO3, it forms a solution of blue colour. Addition of excessof aqueous solution of ammonia to this solution gives _________.

(i) deep blue precipitate of Cu (OH)2

(ii) deep blue solution of [Cu (NH3)4]2+

(iii) deep blue solution of Cu(NO3)2

(iv) deep blue solution of Cu(OH)2.Cu(NO3)2

In a cyclotrimetaphosphoric acid molecule, how many single and doublebonds are present?

(i) 3 double bonds; 9 single bonds

(ii) 6 double bonds; 6 single bonds

(iii) 3 double bonds; 12 single bonds

(iv) Zero double bonds; 12 single bonds

Which of the following elements can be involved in pπ–dπ bonding?

(i) Carbon

(ii) Nitrogen

(iii) Phosphorus

(iv) Boron

Which of the following pairs of ions are isoelectronic and isostructural?

Affinity for hydrogen decreases in the group from fluorine to iodine. Which ofthe halogen acids should have highest bond dissociation enthalpy?

(i) HF

(ii) HCl

(iii) HBr

(iv) HI

Bond dissociation enthalpy of E—H (E = element) bonds is given below. Whichof the compounds will act as strongest reducing agent?

(i) NH3

(ii) PH3

(iii) AsH3

(iv) SbH3

On heating with concentrated NaOH solution in an inert atmosphere of CO2,white phosphorus gives a gas. Which of the following statement is incorrectabout the gas?

(i) It is highly poisonous and has smell like rotten fish.

(ii) It’s solution in water decomposes in the presence of light.

(iii) It is more basic than NH3.

(iv) It is less basic than NH3.

Which of the following acids forms three series of salts?

(i) H3PO2

(ii) H3BO3

(iii) H3PO4

(iv) H3PO3

Strong reducing behaviour of H3PO2is due to

(i) Low oxidation state of phosphorus

(ii) Presence of two –OH groups and one P–H bond

(iii) Presence of one –OH group and two P–H bonds

(iv) High electron gain enthalpy of phosphorus

On heating lead nitrate forms oxides of nitrogen and lead. The oxides formedare ______.

(i) N2O, PbO

(ii) NO2, PbO

(iii) NO, PbO

(iv) NO, PbO2

Which of the following elements does not show allotropy?

(i) Nitrogen

(ii) Bismuth

(iii) Antimony

(iv) Arsenic

Maximum covalency of nitrogen is ______________.

(i) 3

(ii) 5

(iii) 4

(iv) 6

Which of the following statements is wrong?

(i) Single N–N bond is stronger than the single P–P bond.

(ii) PH3can act as a ligand in the formation of coordination compoundwith transition elements.

(iii) NO2is paramagnetic in nature.

(iv) Covalency of nitrogen in N2O5is four.

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

(i) [Fe(H2O)5(NO)]2+

(ii) FeSO4.NO2

(iii) [Fe(H2O)4(NO)2]2+

(iv) FeSO4.HNO3

Elements of group-15 form compounds in +5 oxidation state. However,bismuth forms only one well characterised compound in +5 oxidation state.The compound is

(i) Bi2O5

(ii) BiF5

(iii) BiCl5

(iv) Bi2S5

On heating ammonium dichromate and barium azide separately we get

(i) N2in both cases

(ii) N2with ammonium dichromate and NO with barium azide

(iii) N2O with ammonium dichromate and N2with barium azide

(iv) N2O with ammonium dichromate and NO2with barium azide

In the preparation of HNO3, we get NO gas by catalytic oxidation of ammonia.The moles of NO produced by the oxidation of two moles of NH3will be ______.

(i) 2

(ii) 3

(iii) 4

(iv) 6

The oxidation state of central atom in the anion of compound NaH2PO2willbe ______.

(i) +3

(ii) +5

(iii) +1

(iv) –3

Which of the following is not tetrahedral in shape?

(i) NH4+

(ii) SiCl4

(iii) SF4

(iv) SO42–

Which of the following are per oxoacids of sulphur?

(i) H2SO5and H2S2O8

(ii) H2SO5and H2S2O7

(iii) H2S2O7and H2S2O8

(iv) H2S2O6and H2S2O7