For the circuit shown in Figure, which of the following statements are not true?

The potential difference across capacitor plates remains unchanged when switch $S_3$  is closed.  Will the closing of switch  $S_3$  and  $S_1$  the negative charge on  $C_2$  will attract the positive charge on $C_2$thereby maintaining the negative charge on  $C_1$.  The negative charge on  $C_1$  will attract the positive charge on  $C_1$.  No transfer of charge will take place.  Therefore p.d across  $C_1$ and $C_2$  will be $30V$  and $20V$  respectively.