Yes - the part has a Chip Select line that you must control to talk to it. You start by taking it low, this enables data to go back and forth, and when done you bring it back high.
In my examples, I called it SlaveSelect, or SS.
If you had multiple chips, you would wire a separate SS to each chip (from seperate arduino pins, or from pins on a shift regiser for example).
If instead you used the other Atmel 1MB chip, that uses a slightly different scheme, where the chip has some pins that you wire hi/lo and the chip does an address comparison to an address in the message to see if you are talking to it. That chip let you assign 1 of 4 addresses (00,01,10,11) so 4 chips could be used together.
Its commands would look like this:
// start up I2C, uses Analog 5 for Clock, Analog 4 for data
Wire.begin(); // nothing in () because we are the master
// write intensity10 register
Wire.beginTransmission(COMMAND_ADDRESS); // defined in the datasheet
Wire.send(0xEE); // E = 15/16 (max)