List of practice Questions

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

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

Ammonia will not form complex with

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?

Among the following, the optically active compound is

An atom with high electronegativity has

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:

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

Syngas is a mixture of

$20.0 \,kg$ 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

A lone pair of electrons in an atom implies

Adsorption is accompanied by

Amine that cannot be prepared by Gabriel- phthalimide synthesis is

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.