The silicate having one monovalent corner oxygen atom in each tetrahedron unit is:

If $\omega$ is a complex cube root of unity,then $225 + (3\omega + 8\omega^2)^2 + (3\omega^2 + 8\omega)^2 = $

Match List-$I$ with List-$II$ and then select the correct answer from the codes given below the lists:

List-$I$	List-$II$
$A$. Butane $\to$ Isobutane	$a$. Cracking
$B$. Butane $\to$ Lower hydrocarbons	$b$. Isomerisation
$C$. $n$-Heptane $\to$ Toluene	$c$. Reed reaction
$D$. Propane $\to$ $CH_3CH_2CH_2SO_2Cl$	$d$. Aromatisation

When a non-volatile solute is added to a solvent,the vapor pressure of the solvent decreases by $10 \ mm \ Hg$. The mole fraction of the solute in the solution is $0.2$. If the vapor pressure is to be decreased by $20 \ mm \ Hg$,what will be the mole fraction of the solvent?

In almost all Indian metropolitan cities like Delhi,the major atmospheric pollutant$(s)$ is/are:

The concept of chemical evolution is based on