List of practice Questions

For kinetic study of the reaction of iodide ion with \(H _2 O _2\) at room temperature : 
(A) Always use freshly prepared starch solution 
(B) Always keep the concentration of sodium thiosulphate solution less than that of \(KI\) solution 
(C) Record the time immediately after the appearance of blue colour 
(D) Record the time immediately before the appearance of blue colour 
(E) Always keep the concentration of sodium thiosulphate solution more than that of \(KI\) solution Choose the correct answer from the options given below :

A point $P$ moves so that the sum of squares of its distances from the points $(1,2)$ and $(-2,1)$ is $14$. Let $f(x, y)=0$ be the locus of $P$, which intersects the $x$-axis at the points $A , B$ and the $y$-axis at the point $C, D$. Then the area of the quadrilateral $ACBD$ is equal to

Let $f(x)= \begin{cases} x^3-x^2+10 x-7, & x \leq 1 \\ -2 x+\log _2\left(b^2-4\right), & x>1\end{cases}$ Then the set of all values of $b$, for which $f(x)$ has maximum value at $x=1$, is :

The foot of the perpendicular from a point on the circle \(x ^2+ y ^2=1, z =0\) to the plane \(2 x+3 y+z=6\) lies on which one of the following curves ?

If the function $f(x)= \begin{cases} \frac{\log _e\left(1-x+x^2\right)+\log_e\left(1+x+x^2\right)}{\sec x-\cos x}, x \in\left(\frac{-\pi}{2}, \frac{\pi}{2}\right)-\{0\} \\k, \,\,\,\,\, x=0\end{cases}$ is continuous at $x=0$, then $k$ is equal to :

Consider two GPs $2,2^2, 2^3, \ldots$ and $4,4^2$, $4^3, \ldots$ of 60 and $n$ terms respectively. If the geometric mean of all the $60+ n$ terms is $(2)^{\frac{225}{8}}$, then $\displaystyle\sum_{ k =1}^{ n } k ( n - k )$ is equal to :

Match List-I with List-II

The metal salts formed during softening of hardwater using Clark's method are :

Stearic acid and polyethylene glycol react to form which one of the following soaps/detergents ?

The correct stability order of the following diazonium salt is

Drugs used to bind to receptors, inhibiting its natural function and blocking a message are called :

Given below are two statements : Statement I : On heating with \(KHSO _4\), glycerol is dehydrated and acrolein is formed 
Statement II : Acrolein has fruity odour and can be used to test glycerol's presence Choose the correct option

Two capacitors, each having capacitance $40 \mu F$ are connected in series The space between one of the capacitors is filled with dielectric material of dielectric constant $K$ such that the equivalence capacitance of the system became $24 \mu F$ The value of $K$ will be :

Two projectile thrown at $30^{\circ}$ and $45^{\circ}$ with the horizontal respectively, reach the maximum height in same time The ratio of their initial velocities is

A screw gauge of pitch $05 \,mm$ is used to measure the diameter of uniform wire of length $68 \,cm$, the main scale reading is $15\, mm$ and circular scale reading is $7$. The calculated curved surface area of wire to appropriate significant figures is :[Screw gauge has $50$ divisions on the circular scale]

Refining using liquation method is the most suitable for metals with :

Which of the following can be used to prevent the decomposition of $H _2 O _2$ ?

Reaction of \(BeCl _2\) with \(LiAlH _4\) gives: Choose the correct answer from options given below : 

1. \(AlCl _3\)
2. \(BeH _2\)
3. \(LiH\)
4. \(LiCl\)
5. \(BeAlH _4\)
    

Borazine, also known as inorganic benzene, can be prepared by the reaction of 3-equivalents of "$X$" with 6-equivalents of "Y". "X" and "Y", respectively are :

The difference in the reaction of phenol with bromine in chloroform and bromine in water medium is due to :

Which technique among the following, is most appropriate in separation of a mixture of $100\, mg$ of $p$-nitrophenol and picric acid ?

$\dot{ C } l + CH _4 \rightarrow A + B$. $A$ and $B$ in the above atmospheric reaction step are

The dark purple colour of $KMnO _4$ disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is :

The force required to stretch a wire of cross-section $1 cm ^2$ to double its length will be: (Given Yong's modulus of the wire $=2 \times 10^{11} N / m ^2$ )

If the radius of earth shrinks by $2 \%$ while its mass remains same The acceleration due to gravity on the earth's surface will approximately :