List of practice Questions

$1.5\, g$ of a non-volatile, non-electrolyte is dissolved in $50 \,g$ benzene $(K_b\, =\, 2.5\, K kg \,mol^{-1}$ ). The elevation of the boiling point of the solution is $0.75\, K$. The molecular weight of the solute in $g$ $mol^{-1}$ is

Ammonia will not form complex with

A gas mixture contains 50% helium and 50% methane by volume. What is the percent by weight of methane in the mixture ?

Ammonium ion $\left( NH _{4}^{+}\right)$ reacts with nitrite ion $\left( NO _{2}^{-}\right)$ in aqueous solution according to the equation $NH _{4}^{+}(a q)+ NO _{2}^{-}(a q) \longrightarrow N _{2}(g)+2 H _{2} O (l)$ The following initial rates of reaction have been measured for the given reactant concentrations. Which of the following is the rate law for this reaction?

A binary solid has a primitive cubical structure with $B^-$ ions constituting the lattice points and $A^+$ ions occupying $25\%$ of its tetrahedral holes. The molecular formula of the crystal is

An atom with high electronegativity has

For the reaction $ 2{{N}_{2}}{{O}_{5}}(g)\xrightarrow[{}]{{}}4N{{O}_{2}}(g)+{{O}_{2}}(g) $ if the concentration of $ N{{O}_{2}} $ increases by $ 5.2\times {{10}^{-3}} $ M in 100 s then the rate of the reaction is:

IUPAC name of $ C{{H}_{3}}CH=\underset{\begin{align} & | \\ & C{{H}_{2}} \\ & | \\ & C{{H}_{3}} \\ \end{align}}{\mathop{C}}\,C{{H}_{3}} $

Reaction of diborane with ammonia gives initially

Sphalerite is concentrated by

Complete combustion of 0.858 g of compound $ X $ gives 2.63 g of $ C{{O}_{2}} $ and 1.28 g of $ {{H}_{2}}O $ . The lowest molecular weight which $ X $ can have, is:

Adsorption is accompanied by

$20.0 \,kg$ of $N_2(g)$ and $3.0\, kg$ of $H_2(g)$ are mixed to produce $NH_3(g)$. The amount of $NH_3(g)$ formed is

Amine that cannot be prepared by Gabriel- phthalimide synthesis is

A lone pair of electrons in an atom implies

Choose the reaction with negative $\Delta$S value

Excess nitrate in drinking water can cause

Hard acids prefer to combine with

Force of attraction or repulsion between two current carrying wires separated by a distance r is proportional to

An ammeter reads 0 to 10 A. It has negligible resistance.To convert this into voltmeter to read upto 250 V, resistance to be used is

An object of mass \(40\) \(kg\) is raised to a height of \(5\) \(m\) above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.

If each edge of a cube is doubled, 
(i) how many times will its surface area increase 
(ii) how many times will its volume increase

If a box of sweets is divided among 24 children, they will get 5 sweets each. How many would each get, if the number of the children is reduced by 4?

ABC and ADC are two right triangles with common hypotenuse AC. Prove that ∠ CAD = ∠ CBD.

An antifreeze solution is prepared from 222.6 g of ethylene glycol C₂H₆O₂ and 200 g of water. Calculate the molality of the solution. If the density of the solution is 1.072 g mL^–1, then what shall be the molarity of the solution?