Question

For the reaction:

2H2+O2 ----> 2H2O

How many liters of water can be made from 5L of oxygen gas and an excess of hydrogen?

A toy balloon filled with air has an internal pressure of 1.25 atm and a volume of 2.51 liters. If I take the balloon to the bottom of the ocean where the pressure is 95 atm, what will the new volume of the balloon be? How many moles of gas does the balloon hold? Assume temperature is 12 C.

The label on an aerosol spray can contains a warning that the can should not be heated over 130 F because of the danger of explosion due to the pressure increase as it is heated. Calculate the potential volume of the gas contained in a 500.0 mL aerosol can when it is heated from 25 C to 54 C (approximately 130 F), assuming a constant pressure.

A scuba diver inhales a lung-full (350 mL) of air at a depth of 33 ft where the pressure is approximately 2.0 atm and the water temperatute is 18 C. If the driver holds her breath, what volume will the same amount of air occupy at sea level where the pressure is approximately 1.0 atm and the air temperature is 35 C?

Answer 1

1.

2H2+O2 ----> 2H2O

at STP 1 mole = 22.4 L of O2 = 44.8 L of H2O
              
        5 L of O2   = 44.8*5/22.4 = 10 L

volume of water produced = 10 L

2. p1 = 1.25 atm V1 = 2.51 L

    p2 = 95 atm   V2 = ?

V2 = P1*V1/P2 = 1.25*2.51/95 = 0.033 L

No of moles of the gas = PV/RT = 95*0.033/0.0821*285

= 0.134 mole

3. V1 = 500 ml T1 = 298 K

   V2 = ?        T2 = 352 K

V1/T1 = V2/T2

V2 = 500/298*352 = 590.604 ml

4.   p1 = 2 atm T1 = 291 K V1 = 350 ml

n = PV/RT = 2*0.35/0.0821*291 = 0.03 mol

   p2 = 1 atm T2 = 308 K V2 = ?

V2 = nRT/p = 0.03*0.0821*308/1 = 0.76 L