triac controlling AC motor (20 watts)

[ohm3my]

Experts,

Im trying to implement my Wave Generator for my tank.
Im focusing on using my 20w AC motor and make it on/off periodically with 0.5-0.7 second interval.

I want to use c8051 link to a "optical isolator" then to a "triac"

but my question here is if I put c8051 on (logic "1") then triac will turn on, then what happend if I suddenly put c8051 off (logic "0"). Will motor go off with 50Hz 220v AC?!?! Or It will be continue on till motor powering goes down.

Thanks in advance, any suggestion would be appriciating.

[pebe]

Once triggered, a triac will stay switched on until the current through it reduces to zero, even if the trigger voltage to the gate is removed.

So the triac switches off at the end of a half cycle, ie. at the crossover point where the polarity changes.