Question

Suppose that 200 ml of hydrogen is collected over Water at 26 degree centigrade and pressure 750 mm the pressure of water vapour at 26 degree centigrade is 25 mm what is the pressure of dry hydrogen at 26 degree centigrade

Answer 1

Answer:

Given data:

At 26℃,  

The total partial pressure, Ptotal = 750 mmHg

The partial pressure of water vapour, Ph2o = 25 mmHg

To find: the partial pressure of dry hydrogen at 26℃  

Let the partial pressure of dry hydrogen be denoted as “Pdry”.

According to Dalton’s Law of partial pressure,  

Ptotal = Ph2o + Pdry

∴ Pdry

= Ptotal - Ph2o

= 750 – 25

= 725 mmHg

= 725/760 atm

= 0.953 atm …… [since 1 atm = 760 mmHg]

Hence, the partial pressure of dry hydrogen at 26 degree celcius is 725 mmHg or 0.953 atm.