Amphoteric oxide is:

1) Al₂O_3?
2) SiO₂?
3) P_4?O₁₀?  
4) ClO₇

Among the ligands NH₃, en, CN^– and CO the correct order of their increasing field strength, is:  
 

An ion with 5 protons, 6 neutrons, and a charge of 3+ has an atomic number of
 
 1. 5
 2. 6
 3. 8
 4. 11

Which of the following compounds will exhibit geometrical isomerism

1) 1-Phenyl-2-butene
2) 3-Phenyl-1-butene
3) 2-Phenyl-1-butene
4) 1,1-Diphenyl -1- propene

In which of the following compounds iron has lowest oxidation state 

20 mL solution of 0.1 M ferrous sulphate was completely oxidised using a suitable oxidising agent. What is the number of electrons exchanged?

1) 1.204 x 10²²
2) 193
3) 1930
4) 1.204 x 10²¹

For decolourisation of 1.5moles of KMnO₄ in acidic medium the moles of H₂O₂ requires:

1) 3/ 2
2) 9 /4
3) 15 / 4
4) 21 / 4 

Assertion : Detergents can easily remove oil and dirt from soiled garments.

Reason : Detergents increase the surface tension of water.

1) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2) Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3) Assertion is correct but Reason is incorrect
4) Assertion is incorrect but Reason is correct

A solution of a metal ion when treated with KI gives a red precipitate which dissolves in excess KI to give a colourless solution. Moreover, the solution of metal ion on treatment with a solution of cobalt (II) thiocyanate gives rise to a deep blue crystalline precipitate. The metal ion is

1) Pb²⁺
2) Hg²⁺
3) Cu²⁺
4) Co²⁺

The enthalpy of combusion of cyclohexane, cyclohexene and H₂ are respectively -3920, 3800 and -241 kL mol^-1. The heat of hydrogenation of cyclohexene is ...

1) -121.0 kJ/mol
2) 121.0 kJ/mol
3)-242.0 kJ/mol
4) 242.0 kJ/mol