In trimeta-phosphate ion, the number of 0 atom P-O-P bonds and unit negative charges are respectively:

• 6,6,3

• 3,6,3

• 9,3,3

• 9,6,3

Which of the following is the laboratory method for synthesis of nitric oxide?

• Reaction of zinc with cold and dilute HNO₃

• Reaction of zinc with concentrated HNO₃

• Reaction of copper with cold and dilute HNO₃

• Heating NH₄NO₃

The basic strengths of conjugate bases of oxyacids ofCl will be in the order.

• ${\mathrm{Cl}}_4^{-}<{\mathrm{ClO}}_3^{-}<{\mathrm{ClO}}_2^{-}<{\mathrm{ClO}}^{-}$

• ${\mathrm{ClO}}_3^{-}<{\mathrm{ClO}}_2^{-}<{\mathrm{ClO}}^{-}<{\mathrm{ClO}}_4^{-}$

• ${\mathrm{ClO}}^{-}<{\mathrm{Cl}}_4^{-}<{\mathrm{ClO}}_3^{-}<{\mathrm{ClO}}_2^{-}$

• ${\mathrm{Cl}}_4<{\mathrm{ClO}}_2^{-}<{\mathrm{ClO}}_3^{-}<{\mathrm{ClO}}^{-}$

Which one of the following phosphorous compound is used during electrode position of metal on rubber and for making pesticides?

• Phosphorus pentachloride (PCl₅)

• Phosphorus (Ill) oxide (P₄O₈)

• Phosphorus M oxide (P₄O₁₀)

• Phosphorus trichloride (PCl₃)

Reduction potential of some ions are given below:

Arrange them in decreasing order of oxidising power.

Ions Reduction : Cl${\mathrm{O}}_4^{-}$ I${\mathrm{O}}_4^{-}$ Br${\mathrm{O}}_4^{-}$

Potential E^v = 1.19 V   E^v = 1.741

Potential E^v / V

• Cl${\mathrm{O}}_4^{-}$ > I${\mathrm{O}}_4^{-}$ < Br${\mathrm{O}}_4^{-}$

• I${\mathrm{O}}_4^{-}$ > Br${\mathrm{O}}_4^{-}$ < Cl${\mathrm{O}}_4^{-}$

• Br${\mathrm{O}}_4^{-}$ < I${\mathrm{O}}_4^{-}$ < Cl${\mathrm{O}}_4^{-}$

• Br${\mathrm{O}}_4^{-}$ < Cl${\mathrm{O}}_4^{-}$ < I${\mathrm{O}}_4^{-}$

606.

Which of the following forms molecular solid?

• SO₂

• SiO₂

• SiC

• Diamond

Conc. H₂SO₄ displaces hydrogen chloride from chlorides because:

• it is stronger acid

• sulphates are less soluble than chlorides

• sulphates are more soluble than chlorides

• HCl is a gas while H₂SO₄ is a liquid

Liquid flow from a higher to a lower level.Which of the following liquids can climb up the walls of the glass vessel in which it is placed?

• Mercury

• Liquid N₂

• Liquid He (II)

• Water

A greenish yellow gas reacts with alkali metal hydroxide to form a halate which can be used in fire works and safety matches. The gas and halate respectively are :

• B₂ , KBrO₃

• Cl₂ , KClO₃

• I₂ , NaIO₃

• Cl₂ , NaClO₃

When plants and animals decay, the organic nitrogen is converted into inorganic nitrogen. The inorganic nitrogen is in the form of :

• ammonia

• elements of nitrogen

• nitrates

• nitrides