List of top Chemistry Questions

The ??pin-only??magnetic moment [in units of Bohr magneton,$\left(\mu_{\beta}\right)$ ] of $Ni^{2+}$ in aqueous solution would be (Atomic number of Ni = 28):

What is the $pH$ value of $M H _{2} SO _{4}$ ?

Aqueous solution of $Na_2S_2O_3$ on reaction with $Cl_2$ gives

Three moles of $PCl_5$, three moles of $PCl_3$ and two moles of $Cl_2$ are taken in a closed vessel. If at equilibrium the vessel has $1.5$ moles of $PCl_5$, the number of moles of $PCl_3$ present in it is

Which one of the following pairs is not correctly matched ?

A solution of colourless salt $H$ on boiling with excess $NaOH$ produces a non-flammable gas. The gas evolution ceases after sometime. Upon addition of $Zn$ dust to the same solution, the gas evolution restarts. The colourless salt(s) $H$

The correct statement(s) concerning the structures $E, F$ and $G$ is/are

When a concentrated solution is diluted by adding more water, molarity of the solution remains unchanged. Product of moles of a solute and volume is equal to the molarity.

The pH of a $0.001 \,M$ solution of $ HCl $ is

Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is 100 $\Omega$. The conductivity of this solution is $1.29 S m^{-1}.$. Resistance of the same cell when filled with 0.2 M of the same solution is 520 $\Omega$. The molar conductivity of 0.02 M solution of the electrolyte will be:

The effect of temperature on reaction rate is shown by

$N _{2}(g)+3 H _{2}(g) \rightleftharpoons 2 NH _{3}(g)+22\, kcal$. The activation energy for the forward reaction is $50\, kcal$. What is the activation energy for the backward reaction?

Acid hydrolysis of sucrose is a

In the respect of the equation $ k=A{{e}^{-{{E}_{a}}/RT}} $ in chemical kinetics, which one of the following statements is correct?

For a first order reaction, to obtain a positive slope, we need to plot {where $[A]$ is the concentration of reactant $A$}

The following mechanism has been proposed for the reaction of NO with $Br_{2}$to form NOBr : $NO\left(g\right)+Br_{2} \left(g\right) \text{rightleftharpoons} NOBr_{2} \left(g\right)$ $NOBr \left(g\right)+NO \left(g\right) \to 2NOBr \left(g\right)$ If the second step is the rate determining step, the order of the reaction with respect to NO (g) is:

The radioactivity of a sample is $ {{R}_{1}} $ at a time $ {{T}_{1}} $ and $ {{R}_{2}} $ at times $ {{T}_{2}} $ . the half-life of the specimen is $T$, the number of atoms that have disintegrated at the time $ ({{T}_{2}}-{{T}_{1}}) $ is proportional to

An unknown element forms an oxide. What will be the equivalent weight of the element if the oxygen content is $20\%$ by weight?

$1$ mole of methyl amine on reaction with nitrous acid gives at $NTP$

1.520 g of hydroxide of a metal on ignition gave 0.995 g of its oxide. The equivalent weight of the metal is

During electrolysis of water the volume of $O _{2}$ liberated is $2.24\, dm ^{3}$. The volume of hydrogen liberated, under same conditions will be

Mass of acetic acid required to neutralize 100 cc of 0.1 N NaOH solution is

The number of moles of oxygen obtained by the electrolytic decomposition of $108 \,g$ water is

Number of atoms of $He$ in $100\, u$ of $He$ (atomic wt of $He$ is $4$) are