How to read 24Cxx I2C Eprom bigger than 2Kb (ie 4kb)

Is it a 24C04 ?
They are 4kbit = 512 byte.

You find the first 256 bytes at I2C address 0x50 and the second 256 bytes at 0x51.
The address for the 24C04 is a single byte, not the MSB and LSB you use.

Or is it a 24C32 ?