List of practice Questions

$\dot{ C } l + CH _4 \rightarrow A + B$. $A$ 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 :
During the denaturation of proteins, which of these structures will remain intact ?
The photochemical smog does not generally contain :
Choose the correct order of density of the alkali metals :
The compound(s) that is(are) removed as slag during the extraction of copper is : 
  1. \(CaO\) 
  2.  \(FeO\) 
  3.  \(Al _2 O _3\) 
  4.  \(ZnO\)
  5.  \(NiO\) 
    Choose the correct answer from the options given below :
In two different experiments, an object of mass $5\, kg$ moving with a speed of $25 \,ms ^{-1}$ hits two different walls and comes to rest within
(i) 3 second, 
(ii) 5 seconds, respectively.
Choose the correct option out of the following :
Given below are two statements :
Statement I: In polluted water values of both dissolved oxygen and BOD are very low.
Statement II: Eutrophication results in decrease in the amount of dissolved oxygen.
In the light of the above statements, choose the most appropriate answer from the options given below :
 NCC parade is going at a uniform speed of $9\, km / h$ under a mango tree on which a monkey is sitting at a height of $196\, m$ At any particular instant, the monkey drops a mango A cadet will receive the mango whose distance from the tree at time of drop is : (Given g= 9.8 m/s2)
The dimensions of $\left(\frac{ B ^2}{\mu_0}\right)$ will be :(if $\mu_0$ : permeability of free space andB : magnetic field)
Which one is an amphoteric oxide:
A baby cools from 50°C to 40°C in 5 min. The surrounding temperature is 20°C. In what further time (in minutes) will it cool to 30°C?
A,B and C are voltmeters of resistance R, \(\frac{3}{2}R\) and 3R respectively. When some potential difference is applied between X and Y, the voltmeters readings are VA, VB and VC respectively. Then:
Write down the structure of picric acid
are radish and carrot the root modification?

Volatility of following solutions : H2O , H2Se, H2Te, H2PO

What is Acrolein?

The radius of hydrogen atom in the ground state is 0.53 Å .After collision with an electron it is found to have a radius of 2.1 Å, the principal quantum number 'n' of the state of the atom is 

If you start from the circle and end at the triangle, what is the minimum number of straight lines required to pass through all the dots without retracing any route? You are allowed to pass through a dot more than once.
If you start from the circle and end at the triangle, what is the minimum number of straight lines required to pass through all the dots without retracing any route
Select one of the following four options that will make the 2nd pair analogous to the 1st pair given.
CHOCOLATE: COHCOETAL: ACTOR:?
Each side of a box made of metal sheet in cubic shape is 'a' at room temperature 'T', the coefficient of linear expansion of the metal sheet is ' $\alpha^{\prime}$. The metal sheet is heated uniformly, by a small temperature $\Delta T ,$ so that its new temperature is $T +\Delta T$. Calculate the increase in the volume of the metal box.
Consider the following statements :
Statement 1 : If y = log10x + logex then \(\frac{dy}{dx}=\frac{\log_{10}e}{x}+\frac{1}{x}\)
Statement 2 : \(\frac{d}{dx}(\log_{10}x)=\frac{\log x}{\log 10}\ \text{and}\ \frac{d}{dx}(\log_ex)=\frac{\log x}{\log e}\)
When a car of mass \( m \) is moving with speed \( v \) along a circle of radius \( r \) on a level road, the centripetal force is provided by \( f \), where \( f \) denotes