List of top Chemistry Questions

White phosphorus is heated with concentrated $NaOH$ in $CO _{2}$ atmosphere to form a gas $A$ and compound $B$. When $A$ is bubbled into aqueous $CuSO _{4}$ solution copper phosphide and $C$ are formed, $B$ and $C$ are respectively

Which one of the following is not present in the nitration mixture?

$KO _{2}$, reacts with water to form $A, B$ and $C .$ $B$ forms $C$ when it reacts with iodine in basic medium. What are $B$ and $C$ respectively?

$KMnO _{4}$ oxidises $S _{2} O _{3}^{2-}$ to $SO _{4}^{2-}$ in medium $x$ and $NO^{-}_2$ to $NO^{-}_3$ in medium $y, x$ and $y$ are respectively

Noble metals like gold and platinum are soluble in which of the following mixtures?

Which of the following metals exist in liquid state duiing summer season?

The walls of a closed cubical box of edge $60\, cm$ are made of material of thickness $1\, mm$ and thermal conductivity $4 \times 10^{-4} \; cal \; s^{-1} \; cm^{-1} {^{\circ}C^{-1}}$. The interior of the box is maintained $1000 \; {^{\circ}C}$ above the outside temperature by a heater placed inside the box and connected across $400\, V\, DC$ supply. The resistance of the heater is

Which of the following are carbonate ores? l) Magnetite II) Kaolinite III) Siderite IV) Calamine

Which one of the following has maximum number of hybrid orbitals ?

Observe the following molecules. $PCl_5, BrF_5, ClF_5, PF_5, ClF_3, XeF_4, XeF_2, IF_5 $ The number of molecules having square pyramidal geometry from the above is

The reaction in which $\Delta H > \Delta U$ is

Which of the following orders are correct against the property given? I) dipole moment : $NF_3 > NH_3 >BF_3$ II) Covalent bond length : $C - O > N - O > O - H$ III) Bond order : $C_2 > B_2 > He_2$

The mass of AgCl precipitated when a solution containing 11.70 g of NaCl is added to a solution containing 3.4 g of AgNO3 is [Atomic mass of Ag = 108, Atomic mass of Na = 23]

The number of structural isomers for $ {C_6H_{14}}$ is

A non-volatile solute, ?A? tetramerises in water to the extent of 80%. 2.5 g of ?A? in 100 g of water, lowers the freezing point by 0.3 ?C. the molar mass of ? in mol L-1 is (Kf for water = 1.86 K kg mol-1)

An aqueous solution of CuSO4 is subjected to electrolysis using inert electrodes. The pH of the solution will

Among the following, the main reactions occurring in blast furnace during extraction of iron from haematite are 1. $Fe_{2}O_{3} + 3CO \to 2Fe + 3CO_{2}$ 2. $FeO + SiO_{2} \to FeSiO_{3}$ 3. $Fe_{2}O_{3} + 3C \to 2Fe + 3CO$ 4. $CaO + SiO_{2} \to CaSiO_{3}$

Cis-1, 4-polyisoprene is called

The number of moles of electron required to reduce 0.2 mole of Cr2O-27 to Cr+3

The conformations of n-butane, commonly known as eclipsed, gauche and anti-conformations can be interconverted by

Identify the equation in which change in enthalpy is equal to change in internal energy

Veronal is used as a/an

The volume of $1$ mole of any pure gas at standard temperature and pressure is always equal to

Limestone is used as a flux in the extraction of

Standard hydrogen electrode $(SHE)$ is a