HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

What is the action of 2,4-Dinitrophenylhydrazine on Acetone?

Molar conductivities at infinite dilution of Mg²⁺ and Br^- are 105.8 Ω^-1 cm2 mol^-1 and 78.2 Ω^-1 cm² mol^-1 respectively. Calculate molar conductivity at zero concentration of MgBr₂.

Write the name of reactant used for preparation of phenol, which is given by product used as solvent.

Calculate the atom economy of the following:

(At mass of C = 12, H = 1, 0 = 16)

\[\ce{CH3 - CH2 - OH ->[\Delta] CH2 = CH2 + H2O}\]

How does a catalyst differ from reaction intermediate?

A conductivity cell filled with 0.02 M AgNO₃ gives at 25°C resistance of 947 ohms. If the cell constant is 2.3 cm^-1, what is the molar conductivity of 0.02 M AgNO₃ at 25°C?

Explain the trend in atomic radius of group 18 elements.

Explain the trend in the bond dissociation enthalpies of halogen molecules. Why melting and boiling points of halogens increase on moving down the group?

Explain why transition elements with electronic configuration 3d⁴4s² and 3d⁹4s² do not exist.

The half-lives of a first-order reaction are 1.19s at 313 K and 15.45s at 293 K. Calculate the energy of activation.

Write the preparation of viscose rayon.

The unit of rate constant of zero order reaction is ______.

According to Lowry-Bronsted concept, base is a substance which acts as ______.

What is the SI unit of molar conductivity?

Give the primary and secondary valencies of cobalt in the coordination compound [Co(NH₃)₆]Cl₃.

Find out the oxidation state of cobalt ions in the complex [Co(NH₃)₅Br]S0₄.

How is phenol (carbolic acid) prepared from aniline (diazotization)?

Identify the compo ds A and B in the following reactions:

\[\ce{A ->[Nitrating mixture] B ->[(i) Sn/cone. HCI][(ii) NaOH] Aniline}\]

Explain Swartz reaction.

Mention the res of the following solid:

Ice