Question & Answer

If tan A - tan B = x and cot A - cot B = y then what is the value of cot (A - B)?

The value of  is :

The value of the expression is equal to

If cos  = 2cos then the value of  is equals to

Which of the followings is not equals to unity?

is eqal to?

The value of the expression is

The value of is:

If = (1+2^-x)^-1 and = (1+2^1+x)^-1 then the value of is equal to:

Let and

If , then k is equals to

If = 0 and if = then what is the value of k?

The value of the expression  is ?

Let k = 4 cosx cos2x cos3x - cosx cos2x cos3x then k is equals to

What is the value of (1 + cot θ - cosec θ)(1 + tan θ + sec θ)?

A pressure cooker reduces cooking time for food because:

The enthalpy change for a reaction does not depend upon the:

If at 298K the bond energies of C--H, C-C, C = C, and H-H bonds are respectively 414, 347, 615, and 435 kJ  mol^-1. The value of enthalpy change for the reaction

H₂C = CH₂(g) + H₂(g) -->H₃C - CH3₃(g) at 298K will be:

The correct relationship between free energy change in a reaction and the corresponding equilibrium constant K_c is :

25mL of a solution of barium hydroxide on titration with 0.1 molar solution of hydrochloric acid gave a titer value of 35 mL. The molarity of barium hydroxide solution was :

The rate law for a reaction between the substances A and B is given by rate = k [A]ⁿ[B]^m. On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as :

In a 0.2 molal aqueous solution of a weak acid H X, the degree of ionization is 0.3. Taking K_f for water as 1.85, the freezing point of the solution will be nearest to: 

For the redox reaction

Zn(s) + cu²⁺  (0.1 M) --> Zn²⁺  (1M) + Cu(s)

taking place in a cell, E⁰_cell   is 1.10 volt. E_cell  for the cell will be:

When during electrolysis of a  solution of AgN0₃, 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be

The solubility in water of a sparingly soluble salt AB2 is 1.0 x 10^-5 mot U¹. Its solubility product number will be

For the reaction equilibrium, 

the concentrations of N₂O₄ and NO₂ at equilibrium are 4.8 x 10^-2 and 1.2 x 10^-2 mol L^-1 respectively. The value of K_c for the reaction is:

What volume of hydrogen gas, at 273K and 1 atm pressure will be consumed in obtaining 21.6g of elemental boron (atomic mass 10.8) from the reduction of boron trichloride by hydrogen?

Consider the reaction equilibrium

On the basis of Le-Chatelier's principle, the condition favorable for the forward reaction is

The atomic numbers of vanadium (V), chromium (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24, 25 and 26. Which one of these may be expected to have the highest second ionization enthalpy?

The pair of species having identical shapes for molecules of both species is

In the anion HCOO^- the two carbon-oxygen bonds are found to be of equal length. What is the reason for it?

Which one of the following groupings represents a collection of isoelectronic species?

(At. numbers : Cs-55, Br-35)

Which of the following pairs of molecules will have permanent dipole moments for both members?

Which one of the following compounds has the smallest bond angle in its molecule?

Which one of the following processes will produce hard water?

Among the following four structures I to IV, which one is true?

Ether is more volatile than alcohol having the same molecular formula. This is due to

The general formula C_nH_2nO₂ could be for open-chain: 

Which of the following group of transition metals is called coinage metals? 

According to the kinetic theory of gases in an ideal gas, between two successive collisions a gas molecule travels: 

When is reduced with LiAlH₄, the compound obtained will be 

The IUPAC name of CH₃COCH(CH₃)₂ is

Graphite is a soft solid lubricant extremely difficult to melt. The reason for this anamalous behavior is that :