List of top Chemistry Questions

A complex involving $dsp^2$ hybridisation has
A combustible gas is liberated when caustic soda solution is heated with
A colloid always :
A colloidal system having a solid substance as a dispersed phase and a liquid as a dispersion medium is classified as_____________ .
A chemical $'A?$ is used for the preparation of washing soda to recover ammonia. When $CO_2$ is bubbled through an aqueous solution of $'A?$, the solution turns milky. It is used in white washing due to disinfectant nature. What is the chemical formula of $'A'$ ?
A chelating agent has two or more than two donor atoms to bind to a single metal ion. Which of the following is not a chelating agent?
A certain current liberate 0.5 g of hydrogen in 2 h. How many grams of copper can be liberated by the same current flowing for the same time in a copper sulphate solution ?
A certain compound $X$ imparts a golden yellow flame. When zinc powder is heated with concentrated solution of $X$, $H_2$ gas is evolved. $X$ combines with $CO_2$ to give a salt $Y$. $Y$ is a hydrated salt which on reaction with $HCl$ or excess of $CO_2$ gives another salt $Z$ which is an important part of baking powder. Identify $X$, $Y$ and $Z$.
A certain compound has a formula $ {C_3H_6O}$. It combines with hydroxylamine to form two compounds which are geometrical isomers of each other. It is
A box of T L-capacity ls'divided into two equal compartments by a thin partition which are filled with 2 g $H_2$ and 16 g $CH_4$ respectively. The pressure in compartment filled with $H_2$ is recorded as P atm. The total pressure when partition is removed will be
A black powder when heated with cone. $HCl$ gives a greenish yellow gas. The gas acts as an oxidising and a bleaching agent. When it is passed over slaked lime, a white powder is formed which is a ready source of gas. The black powder and white powder respectively are
A black compound of manganese reacts with a halogen acid to give greenish yellow gas. When excess of this gas reacts with $NH_3$ an unstable trihalide is formed. In this process the oxidation state of nitrogen changes from
A barbituric acid derivative drug Veronal is used as
How many radial nodes are there in 5f orbital ?
A 500 g toothpaste sample gas 0.2 h fluoride concentration. What is the concentration of $F^-$ ions in terms of ppm level ?
A 2.24 L cylinder of oxygen at N.T.P. is found to develop a leakage. When the leakage was plugged the pressure dropped to 570 mm of Hg. The number of moles of gas that escaped will be
A $100$ watt bulb emits monochromatic light of wavelength $400\,nm$. Calculate the number of photons emitted per second by the bulb.
A $0.5\, dm^3$ flask contains gas $A$ and $1 \,dm^3$ flask contains gas $B$ at the same temperature. If density of $A = 3.0\, g\, dm^{-3}$ and that of $B = 1.5\, g\, dm^{-3}$ and the molar mass of $A=\frac{1}{2}$ of $B$, then the ratio of pressure exerted by gases is
96500 C electricity is passed through $CuSO_4$. The amount of copper precipitated is
8.2 L of an ideal gas weighs 9.0 g at 300 K and 1 atm. pressure. The molecular mass of gas is
7.5 grams of a gas occupy 5.6 litres of volume at STP. The gas is (Atomic weights of C, N and O are 12, 14 and 16 respectively)
50 mL of gas A effuses through a pin hole in 146 seconds. The same volume of $CO_2$ under identical condition effuses in 115 seconds. The molar mass of A is
4.48 litres of an ideal gas at STP requires 12.0 calories to raise its temperature by 15$\circ$C at constant volume. The $C_p$ of the gas is
3-hydroxy butanal is formed when X reacts with Y in dilute Z solution. What are X, Y and Z?
$ {2CuFeS_2 + O_2 -> Cu_2S + 2FeS + SO_2}$ Which process of metallurgy of copper is represented by above equation?