i have to glow bulb using salty water. so for how much time will it remain glow

 

I think you will find that producing current will take more than just salt water.

 

sorry couldn't understand

 

ok tell me that edison faced the problem regarding the oxygen gas due to the absence of which the filament can;t glow. so tell me that there is also no gas present inside a bulb so then how it continues to glow.

 

the problem that edison ran into (in my understanding - I could be completely wrong) is that in the presence of oxygen, the filament would oxidize and break/burn. It was the lack of oxygen which allowed the filament to last for an extended period of time.

 

Edison's bulbs were pumped down to a hard vacuum to preserve the filament. Modern bulbs are full of argon gas.

I had assumed that the salty water was for an electrochemical cell to produce current. If not, what about the salt water is going to make the bulb glow?

 

thans dude