List of top Chemistry Questions

$X Cl _{2}( excess )+Y Cl _{2} X Cl _{4}+Y \downarrow$ $Y O {->[{\Delta}][{>400^{\circ} C }]} \frac{1}{2} O _{2}+Y$ Ore of Y would be ,

Consider the following changes $M(s) \longrightarrow M(g)$ $M(g) \longrightarrow M^{2+}(g)+2 e^{-}\ldots$(1) $M(g) \longrightarrow M^{+}(g)+e^{-}\ldots$(2) $M^{+}(g) \longrightarrow M^{2+}(g)+e^{-} \ldots$ (3) $M(g) \longrightarrow M^{2+}(g)+2 e^{-}\ldots$(4) The second ionisation energy of $M$ could be determined from the energy values associated with

If the ionisation energy and electron affinity of an element are $275$ and $86 \,kcal\, mol^{-1}$ respectively, then the electronegativity of the element on the Mulliken scale is

With excess of water, both $P_{2}O_{5}$ and $PCl_{5}$ give

Which one of the following is a case of negative adsorption?

A certain metal when irradiated by light $(r = 3.2 \times 10^{16} Hz)$ emits photoelectrons with twice kinetic energy as did photoelectrons when the same metal is irradiated by light $(r =2.0 \times 10^{16} Hz)$. The $v_0$ of metal is

An alloy of copper, silver and gold is found to have copper atom constituting the ccp lattice. If silver atom occupy the edge centres and gold atom is present at body centred, the alloy has a formula

Two Faraday of electricity is passed through a solution of $CuSO_4$. The mass of copper deposited at the cathode is (At. mass of $Cu\, = \,63.5\, u$)

Determination of the molar mass of acetic acid in benzene using freezing point depression is affected by :

Gaseous $N_2O_4$ dissociates into gaseous $NO_2$ according to the reaction $N _{2} O _{4}( g ) \rightleftharpoons 2 NO _{2}( g )$ At $300\, K$ and $1\, atm$ pressure, the degree of dissociation of $N_2O_4$ is $0.2.$ If one mole of $N_2O_4$ gas is contained in a vessel, then the density of the equilibrium mixture is :

In Carius method of estimation of halogens $250\, mg$ of an organic compound gave $141\, mg$ of $AgBr$. The percentage of bromine in the compound is (atomic mass $Ag\, =\, 108, Br \,= \,80$)

The current voltage relation of diode is given by $I=\left(e^{1000 V / T}-1\right) mA$, where the applied voltage $V$ is in volt and the temperature $T$ is in kelvin. If a student makes an error measuring $\pm 0.01\, V$ while measuring the current of

The following reaction is performed at $298\, K ?$ $2 NO ( g )+ O _{2}( g ) \rightleftharpoons 2 NO _{2}( g )$ The standard free energy of formation of $NO ( g )$ is $86.6 \,kJ /\, mol$ at $298 \,K .$ What is the standard free energy of formation of $NO _{2}( g )$ at $298 \,K ?\left( K _{n}=1.6 \times 10^{12}\right)$

The molecular formula of a commercial resin used for exchanging ions in water softening is $C_8H_7SO_3Na$ (molecular weight = $206$). What would be the maximum uptake of $Ca^{2+}$ ions by the resin when expressed in mole per gram resin

The $pH$ of a solution obtained by mixing of $100\, mL$ of a $HCl$ solution of $pH = 2$ with $400\, mL$ of another $HCl$ solution of $pH = 3$ will be

The common name of $K \left[ PtCl _{3}\left(\eta^{2} \cdot C _{2} H _{4}\right)\right]$ is:

Polymer used in bullet proof glass is

Thomas slag is

One of the lines in the emission spectrum of $Li ^{2+}$ has the same wavelength as that of the $2^{\text {nd }}$ line of Balmer series in hydrogen spectrum. The electronic transition corresponding to this line is $n =12 \rightarrow n = x$. Find the value of $x$.

The prefix $10^{18}$ is

The carbylamine reaction is

The by product of Solvay-ammonia process is

The color of $CoCl _{3} \cdot 5 NH _{3} \cdot H _{2} O$ is

Which of the following represents hexadentate ligand?

Cobalt $(60)$ isotope is used in the treatment of :