How many moles of aluminum oxide $(Al_2O_3)$ are produced when $1 \text{ mole}$ of potassium chlorate $(KClO_3)$ undergoes thermal decomposition,and the resulting gaseous product is reacted with excess aluminum?

The incorrect postulates of the Dalton's atomic theory are :
$A$. Atoms of different elements differ in mass.
$B$. Matter consists of divisible atoms.
$C$. Compounds are formed when atoms of different element combine in a fixed ratio.
$D$. All the atoms of given element have different properties including mass.
$E$. Chemical reactions involve reorganisation of atoms.
Choose the correct answer from the options given below :

$10 \ g$ $NaHCO_{3(s)}$ sample is heated in open to constant weight,the residue is titrated against $0.1 \ M \ HCl$ in presence of phenolphthalein as an indicator,$500 \ mL$ of acid was required to reach end point hence $PERCENT$ purity of sample is $............... \%$.

Ferric alum has the composition $(NH_4)_2SO_4 \cdot Fe_2(SO_4)_3 \cdot xH_2O$,where $x$ is..........

What is $Rasavidya$?

When $100 \ mL$ of $1 \ M \ NaOH$ solution and $10 \ mL$ of $10 \ N \ H_2SO_4$ solution are mixed together,the resulting solution will be