A, B and D should be the ones you should check
chlorobenzene
Carbon - 6
Hydrogen - 5
Chlorine - 1
that 1 chlorine replaces one of the hydrogens
thats why hydrogen number decreases by number of Cl atoms (that are substituting those H atoms)
Ethanol will evaporate first because it is more volatile or has a lower boiling point than water.
No of protons=107+1=108
No. Of neutrons=158
Mass no. =166
