Consider the following statements:

(I)$\mathrm{Mass} \mathrm{percent} = \frac{\mathrm{Mass} \mathrm{of} \mathrm{solute}}{\mathrm{Mass} \mathrm{of} \mathrm{solvent} }\times 100$

(II) 200 mL of 1M NaOH is diluted to 1L solution, the number of moles of solute remains the same.

(III)The element having the highest mass percentage in C₂H₅OH is carbon.

(IV) The number of moles of solute present in 1 kg of solution is molality.

Among these, the correct statements are,