Iron sulphide is heated in air to form $A$,an oxide of sulphur. $A$ is dissolved in water to give an acid. The basicity of this acid is

What is $Rasavidya$?

$10 \ g$ $NaHCO_{3(s)}$ 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 $............... \%$.

Which sample contains the largest number of atoms?

$250 \, mL$,$6 \, M$ $HCl$ and $350 \, mL$,$8 \, M$ $HNO_3$ are mixed with water to make the strength of the resulting solution $3 \, N$. What is the volume of water added? $mL$

What is the composition of the white enamel of our teeth?