List of top Chemistry Questions

KBr crystallises in NaCl type of crystal lattice and its density is 2.75 g/cm$^3$. Number of unit cells of KBr present in a 1.00 mm$^3$ grain of KBr are
Find the pressure of a sample of CCl$_4$ if 1.0 mole occupies 35 L at 77$^\circ$C. Assume CCl$_4$ obeys the van der Waals equation of state. ($a = 20$, $b = 0.14$)
Which one of the following is the weakest acid?
The high oxidising power of fluorine is due to its
The element which forms ions in dimeric state is
Due to lanthanide contraction
Gold is extracted by hydrometallurgical process, based on its property
Which of the following species contain an element in an oxidation state that is not a whole number?
For the reaction represented by the equation, \[ CX_4 + 2O_2 \rightarrow CO_2 + 2X_2O \] 9.0 g of CX$_4$ completely reacts with 1.74 g of oxygen. The approximate molar mass of X will be
An aqueous solution of phosphoric acid, H$_3$PO$_4$ being titrated has molarity equal to 0.25 M. Which of the following could be normality of this solution?
Which of the following processes does not yield a primary amine?
How many enols (including stereo isomers) exist for 3-hexanone?
Which of the following compounds will not react with Mg metal in the presence of ether to give a Grignard reagent?
Circular divisions = 50, pitch = 0.5 mm. Find diameter.
Given a sample of radium-226 having half-life of 4 days. Find probability that a nucleus disintegrates after 2 half-lives.
Ratio of wavelengths for \(2\to1\) transition in Li\(^+\), He\(^+\), and H is
In photoelectric effect, if wavelength changes from \(\lambda\) to \(3\lambda/4\), how does max speed change?
Minimum intensity of light detectable is \(10^{-10}\,W/m^2\). Number of photons entering eye per second (\(\lambda=5.6\times10^{-7}m\), pupil area \(10^{-6}m^2\)).
De-Broglie wavelength of neutron at \(27^\circ C\) is \(\lambda\). Find at \(927^\circ C\).
Equal masses of $H_2, O_2$ and methane have been taken in a container of volume V at temperature $27^\circ$C in identical conditions. The ratio of the volumes of gases ${H_2 : O_2 :CH_4}$ would be
When 22.4 litres of H2(g) is mixed with 11.2 litres of Cl2 (g), each at S.T.P., the moles of HCl (g) formed is equal to :
(a) ${H_2 O_2 + O_3 -> H_2O + 2O_2}$ (b) ${H_2 O_2 + Ag_2O -> 2Ag + H_2O + O_2}$ Role of hydrogen peroxide in the above reactions is respectively -
Among the following complexes, the one which shows zero crystal field stabilisation energy (CFSE) is
For a given exothermic reaction, $K_p$ and $K_p'$ are the equilibrium constants at temperatures $T_1$ and $T_2$, respectively. Assuming that heat of reaction is constant in temperature range between $T_1$ and $T_2$, it is readily observed that :-
In acidic medium, $H_2O_2 $ changes $ Cr_2O_7^{2-} $ to $CrO_5 $ which has two (-O-O-) bonds. Oxidation state of Cr in $CrO_5 $ is