$100 \ mL$,$1 \ M$ $H_2SO_4$ solution of density $1.5 \ g/mL$ is mixed with $400 \ mL$ of water,resulting in a diluted solution of density $1.25 \ g/mL$. Find the molarity of the final diluted solution. (Density of water $= 1 \ g/mL$)

State whether the following statements are true or false:
$(i)$ The molarity of a $0.6 \ N$ aqueous solution of ${H_3PO_3}$ is $1.2 \ M$.
$(ii)$ $\text{Empirical formula} = n \times \text{Molecular formula}$.
$(iii)$ In ${Cl_2O}$,the weight of chlorine combining with $8 \ g$ of oxygen is $35.5 \ g$.

When a standard solution of $NaOH$ is left in air for a few hours,

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:

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 :

$K_2CS_3$ is called potassium ...... .