Below is the code you use to find I2C device addresses on an Arduino device.   On a Raspberry Pi you use I2CDevice -y 1.    Raspberry Pi has two I2C buses.   Bus 0 is used for a HAT device on top of a Pi.   Bus 1 is used for I2C communication.   You will see in my setup I have a Bi Directional Logic Level chip to convert 3.3V to 5V devices. 

Scanning…
I2C Address is 0x05 !
I2C Address is 0x06 !
I2C Address is 0x07 !
I2C Address is 0x09 !
I2C Address is 0x0A !
I2C Address is 0x0B !
I2C Address is 0x0C !
Done

Raspberry Pi  Terminal I2Cdetect -y 1.    SMBus(1) is the I2C bus you communicate with.

$ i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          — 04 05 06 07 08 09 0a 0b 0c — — —
10: — — — — — — — — — — — — — — — —
20: — — — — — — — — — — — — — — — —
30: — — — — — — — — — — — — — — — —
40: — — — — — — — — — — — — — — — —
50: — — — — — — — — — — — — — — — —
60: — — — — — — — — — — — — — — — —
70: — — — — — — — —                         
pi@raspberrypi:~ $