Question

A sample of nitrogen monoxide occupies a volume of 400 mL at 100 °C and 720 mmHg.

Answer 1

The volume of nitrogen  monoxide that   occupy  at  STP  is=  277  Ml

     calculation
 The volume is obtained  using   the combined  gas law  that is P1V1/T1= P2V2?
Where  P1 = 720  MmHg
            V1 = 400ml
           T1= 100 +273=  373 K
At  STP  temperature  =  273 K  and  pressure=  760 mm  hg
therefore T2=  273 k
               p2 = 760  mmhg
               V2=?
make  V2  the subject of the formula

V2= (T2 ×P1 ×V1)/(P2×T1)

V2  is therefore  = (273k  x720 mmhg x 400 ml)/(760 mmhg x373K) = 277  Ml