List of top Chemistry Questions

Reaction of carbonyl compound with one of the following reagents involves nucleophilic addition followed by elimination of water. The reagent is :

The correct bond order in the following species is :

The boiling point of 0.2 mol kg$^{-1}$ solution of X in water is greater than equimolal solution of Y in water. Which one of the following statements is true in this case ?

The angular momentum of electron in 'd' orbtial is equal to

Permanent hardness in water cannot be cured by :

Which one of the following alkaline earth metal sulphates has its hydration enthalpy greater than its lattice enthalpy?

Solubility of the alkaline earth?? metal sulphates in water decreases in the sequence :

The reaction is called :

What is the mass of the precipitate formed when 50 mL of 16.9% solution of $AgNO_3$ is mixed with 50 mL of 5.8% $NaCl$ solution ? (Ag = 107.8, N = 14, O = 16, Na = 23, Cl =35.5)

Which physical property of dihydrogen is wrong ?

Addition of phosphate fertilisers to water bodies causes :

In the long form of the periodic table, the valence shell electronic configuration of $5s^2 5p^4$ corresponds to the element present in :

The least number of oxyacids are formed by :

Rachel Carson's famous book 'Silent Spring ' is related to

Which of the following pairs of ions are isoelectronic and isostructural ?

A mixture of methylamine and dimethylamine is given to you. The reagents used to separate the components of the mixture are

The distinguishing test between methanoic acid and ethanoic acid is

Half-life period of a first order reaction is $10\, min$. Starting with initial concentration $12\, M$, the rate after $20\, min$ is

Molar enthalpy change for melting of ice is $6\, kJ / mol$. Then the internal energy change (in $k J / mol$ ) when $1$ mole of water is converted into ice at $1$ atm at $0^{\circ} C$ is Empty QImg

Which of the following options represents the correct bond order ?

How does the electron gain enthalpies vary across a period and down a group?

The number of $Na$ atom in $46\, g \,Na$ (atomic weight of $Na= 23$) is

If the solubility of a sparingly soluble salt $AX _{2}$ is $s\, mol / L$, the solubility product is

Among $P, S, Cl, F$, the elements with most negative and least negative electron gain enthalpy respectively, are

The species which cannot serve as an initiator for the free radical polymerisation, is