Volume of nitrogen gas is 125ml atmospheric pressure is 763mm Hg the water temperature inside the eudiometer is the same as the level of the water in the beaker.

Calculate the volume if the nitrogen at STP.
P1V1/T1=P2V2/T2

That formula will work if you want the volume of the wet nitrogen, if you want the volume of dry N2 gas you will need to correct for that.

To calculate the volume of nitrogen gas at STP (Standard Temperature and Pressure), we can use the combined gas law equation:

P1V1/T1 = P2V2/T2

where:
P1 = initial pressure (atmospheric pressure)
V1 = initial volume (125 ml)
T1 = initial temperature (water temperature in the eudiometer)
P2 = final pressure (STP pressure, which is approximately 1 atm)
V2 = final volume at STP (unknown)
T2 = final temperature at STP (273.15 K)

Now let's substitute the known values into the equation:

P1 = 763 mm Hg (convert to atm: 763 mm Hg / 760 mm Hg = 1.004 atm)
V1 = 125 ml
T1 = temperature of the water in the eudiometer (which is the same as the level of the water in the beaker)

We need to convert the temperature in Celsius to Kelvin for this equation, so if you know the temperature in Celsius, add 273.15. If you provide the temperature in Celsius, I can continue with the calculation.