2 Amps is at low voltage, at 230 V its derated to 25VA which is next to nothing current wise (less than 100 mA ) . Hardly surprising a with a mechanical relay less than the size of your thumb nail.
A simple opto-isolator chip with a triac output will have a similar power handling to that tiny relay, with a lot less grief hooking it to an arduino......
I'll say it again, you have no where near the knowledge required to be playing with mains voltages
