List of top Chemistry Questions on Equilibrium asked in AIIMS

pH of a salt solution of wak acid (pKa = 4) & weak base (pKb = 5) at 25�C is :

When $CH_3COOCH_3 + HCl$ is titrated with $NaOH$ then at neutral point the colour of phenolphthalein becomes colourless from pink due to

In the given reaction : $A + 2B \rightleftharpoons 2C$ moles each of A and B present in 10 L of solution combine to form 1 mole of C. Calculate $K_c$ for the reaction.

For the reaction, $H_{2} + I_{2} {\rightleftharpoons} 2HI, K= 47.6.$ If the initial number of moles of each reactant and product is 1 mole then at equilibrium

The second dissociation constant of fumaric acid is greater than maleic acid. Higher the dissociation constant of acid, more is the acidic character.

$K_a$ for $HCN$ is $5 \times 10^{-10}$ at $25^{\circ}C$. For maintaining a constant $pH\, = \,9$, the volume of $5\, M \,KCN$ solution required to be added to $10 \,mL$ of $2\, M HCN$ solution is

$K_p$ for the reaction $ {A {\rightleftharpoons} B}$ is 4. If initially only A is present then what will be the partial pressure of B after equilibrium ?

A vessel of one litre capacity containing $1$ mole of $SO_3$ is heated till a state of equilibrium is attained. $ {2SO3_{(g)} <=> 2SO2_{(g)} + O2_{(g)}}$ At equilibrium, $0.6 \,moles$ of $SO_2$ had formed. The value of equilibrium constant is

' $a$ ' moles of $PCl _{5}$ are heated in a closed container to equilibriate $PCl _{5}(g) \rightleftharpoons PCl _{3}(g)+ Cl _{2}(g)$ at a pressure of $p$ atm. If $x$ moles of $PCl _{5}$ dissociate at equilibrium, then

Which has the highest pH?

At equilibrium which is correct?

$\frac{K_{p}}{K_{c}}$ for following reaction will be $\quad\quad$$CO_{\left(g\right)}+\frac{1}{2}O_{2\left(g\right)}\rightarrow CO_{2\left(g\right)}$

$K_{sp}$ of $CaSO_4\cdot5H_2O$ is 9 x $10^{-6}$, find the volume for 1 g of $CaSO_4$ (M.wt. = 136).

What is the $pH$ of $0.01\, M$ glycine solution? For glycine $K_{a_1} = 4.5 \times 10^{-3}$ and $K_{a_2} = 1.7 \times 10^{-10}$ at $298 \,K$.

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

According to Le-Chatelier?? principle addition of heat to an equilibrium solid ? liquid results in decrease in the amount of solid. Reaction is endothermic, so on heating forward reaction is favoured.

Mixture of $CH_3COOH$ and $CH_3COONH_4$ is an example of acidic buffer. Acidic buffer contains equimolar mixture of weak acid and its salt with weak base.

$40\, ml$ of $0.1\, M$ ammonia solution is mixed with $20 \,ml$ of $0.1\, M\, HCl$. What is the $pH$ of the mixture? $\left( p K_{b}\right.$ of ammonia solution is $\left.4.74\right)$

When $10\, mL$ of $0.1\, M$ acetic acid $(pK_{a} = 5.0)$ is titrated against $10\, mL$ of $0.1\, M$ ammonia solution $(pK_{b} = 5.0)$, the equivalence point occurs at $pH$

Dimethyl glyoxime gives a red precipitate with $Ni ^{2+}$, which is used for its detection. To get this precipitate readily the best $pH$ range is

Which one of the following is not a buffer solution?

The $pH$ of solution containing $0.10\, M$ sodium acetate and $0.03\, M$ acetic acid is $ \left( pK _{a} \text { for } CH _{3} COOH =4.57\right) $

An equilibrium mixture of the reaction $2 H _{2} S _{( s )} \rightleftharpoons 2 H _{2( g )}+ S _{2( g )}$, had $0.5\, mole\, H _{2} S$ $0.10$ mole $H _{2}$ and $0.4$ mole $S _{2}$ in one litre vessel. The value of equilibrium constant $( K )$ in mole litre $^{-1}$ is

A solution wiht $pH = 2$ is more acidic than one with a $pH = 6$, by a factor

A base, as defined by Bronsted theory, is a substance which can