When you write to a serial eeprom there is a delay whilst the write takes place and in this time the chip doesn't respond at all. To ensure the chip is responding you have to wait for an acknowledge after sending the ID (0xa0). If no ACK is received you have to send a stop and do it all again.
Assuming the library routines you are using return a boolean to signify ACK/NACK then something like this should work.
Hi thanks pommie for reply. i have tried ur idea, now what is happening is the data is being sent its sends the acklegement that data is sent but it does not recieve it it show me 255 output please help