The basic structural unit of silicates is 

• SiO^-

• SiO₂^4-

• SiO₃^2-

• SiO₃^2-

Which of the following is electron deficient

• (CH₃)₂

• (SiH₃)₂

• (BH₃)₂

• (BH₃)₂

Structure of the compound whose IUPAC name is 3-ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid is

The order of stability of the following tautomeric compound is 

• I>Ii>III

• III > II>I

• Ii> I> III

• Ii> I> III

The radical  because it has

• 6 p -orbitals and 6 unpaired electrons

• 7 p- orbitals and 6 unpaired electrons

• 7 p- orbitals and 7 unpaired electrons

• 7 p- orbitals and 7 unpaired electrons

The structure of isobutyl group in an organic compound is

What is the activation energy for a reaction if its rate doubles when the temperature is raised from 20⁰C to 35⁰C ?(R=8.314 J mol^-1 K^-1).

• 342 kJ mol^-1

• 269 kJ mol^-1

• 34.7 kJ mol^-1

• 34.7 kJ mol^-1

At 25⁰ molar conductance of 0.1 molar aqueous solutions of ammonium hydroxide is 9.54 ohm^-1 cm² mol^-1 and at infinite dilution, its molar conductance is 238 ohm^-1 cm² mol^-1. The degree of ionisation of ammonium hydroxide at the same concentration and temperature is 

• 2.080%

• 20.800%

• 4.008%

• 4.008%

19.

A button cell used in watches functions as following

The cell potential will be

• 1.10 V

• 0.42 V

• 0.84 V

• 0.84 V

The number of carbon atoms per unit cell of diamond unit cell is

• 4

• 8

• 6

• 6