Hey there!
* Converts 1750 dm³ in liters :
1 dm³ = 1 L so 1750 dm³ = 1750 liters
* Convertes 125,000 Pa in atm :
1 Pa = 9.86*10⁻⁶ atm so 9.86*10⁻⁶ / 125,000 => 1.233 atm
* Convertes 127ºC in K :
127 + 273.15 => 400.15 K
R = 0.082 atm.L/mol.K
Finally, it uses an equation of clapeyron :
p * V = n * R * T
1.233 * 1750 = n * 0.082 * 400.15
2157.75 = n * 32.8123
n = 2157.75 / 32.8123
n = 65.76 moles
hope this helps!
When the amount of gas in a container is increased, the volume increases. Lussac's law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.
