List of top Chemistry Questions

The $E _{\text {red }}^{\circ}$ of $Ag,\, Cu ,\, Co$ and $Zn$ are $0.799$ $0.337,-0.277$ and $-0.762\, V$ respectively, which of the following cells will have maximum cell emf?

Which is used for sterilization of water in water supply system of cities?

Electrolytic refining is used to purify which of the following metals ?

What will be the $ E_{cell} $ for the given cell ? $ Zn\left|Zn^{2+}\left(0.1\,M\right)\right|\left|Cu^{2+}\left(0.01\,M\right)\right|Cu $ Given : $ E^{\circ}_{Zn^{2+}Zn}=0.76\,V $ and $ E^{\circ}_{Cu^{2+}Cu}=0.34\,V $ . Also predict whether the reaction is spontaneous or non-spontaneous.

The standard emf of the cell $ (E^{\circ}_{cell} $ and equilibrium constant $ (K_{eq}) $ of the following reaction of $ 298\, K $ $ Cd^{2+} + 4NH_{3} {\rightleftharpoons} Cd (NH_{3})^{2+}_{4} $

What is Tg for polymer?

In the reaction NaOH (hot and conc.) + Cl $\to$ NaCl + NaClO Change in oxidation state of Cl is :

Which of the following does not depend on the attraction of the bonding pair towards the nucleus.

What is the maximum wavelength of line of Balmer series of hydrogen spectrum? (R = 1.09 ??10 m)

If $ \chi_{1} $ and $ \chi_{2} $ represent the mole fractions of a component $ A $ in the vapour phase and liquid mixture respectively, and $ p^{\circ}_{A} $ and $ p^{\circ}_{B} $ represent vapour pres sines of pure A and pure B, then total vapour pressure of liquid mixture is

1 g of polymer having molar mass 1,60,000 g is dissolved in 800 mL water. Calculate the osmotic pressure in pascal at 27$^{\circ}$C. $(R \,= \,8.314\, J \,K^{-1}mole^{-1})$

The vapour pressure of a liquid decreases if some non-volatile solute is dissolved in it. The relative lowering of vapour pressure of a solution containing a non-volatile solute is equal to the mole fraction of the solute in the solution.

Ethylene glycol is used as antifreeze to reduce freezing point of water to $-2.4^{\circ}\,C$. What mass of antifreeze is required for $2\, L$ water? $(K_f \,water\, = \,1.86\, K \,kg/mole)$

When pressure is increased at constant temperature

Solution with similar osmotic pressure are called?

In activation energy for a simple Chemical reaction $A \to B$ is $E_{a}$ in forward direction. The activation energy for reverse reaction

For the reaction, $2SO_2 + O_2 <=> 2SO_3, $ the rate of disappearance of $O_2$ is $2 \times 10^{-4} \, mol \, L^{-1} \, s^{-1}$ . The rate of of appearance of $SO_3$ is

Catalyst increase rate of reaction while photosensitizer initiate a reaction. Catalyst decrease E but photosensitizer act as energy carrier

For a first order reaction ${A(g) \to 2B(g) + C(g)}$ at constant volume and $300\, K$, the total pressure at the beginning $(t = 0)$ and at time $t$ are $P_0$ and $P_t$, respectively. Initially, only $A$ is present with concentration $[A]0$, and $t_{1/3}$ is the time required for the partial pressure of $A$ to reach $1/3^{rd}$ of its initial value. The correct option(s) is (are) (Assume that all these gases behave as ideal gases)

The rate constant, the activation energy and the Arrhenius parameter of a chemical reaction at $ 25^{\circ}C $ are $ 3.0 \times 10^{-4} \, s^{-1} $ , $ 104.4 \, kJ \, mol^{-1} $ and $ 6.0 \times 10^{14} \, s^{-1} $ , respectively. The value of the rate constant at $ T \rightarrow \infty $ is

Thermal decomposition of $HCOOH$ is a first order reaction and the rate constant at T(K) is $4.606 \times 10^{-3}\, s^{-1}$. The time required to decompose $90\%$ of initial quantity of $HCOOH$ at $T(K)$ in seconds is

A metal $M$ (specific heat $0.16$) forms a metal chloride with $= 65\%$ chlorine present in it. The formula of the metal chloride will be

How many moles of electron weight one kilogram :

Which statement(s) is (are) false for the periodic classification of elements?