Socrates - Comenius 1: 
School Project “We are all living under the same sky”


Chemistry

LABORATORY WORK No 7

Performed by:

Vojtech Krejska, Lubos Polak, Karel Fical, Jiri Beranek


Conditions:

t = 20.4 °C; p = 1018.5 hPa; φ = 47.3 %


Topic:

Vital Capacity


Tasks:

1.

Measure the volume of lungs of your classmates.

2.

Make up a graph and evaluate its course.


Theory:

Man breaths the air, that contains about 78 % nitrogen N2 a 21 % oxygen O2 . The air oxygen is transferred to haemoglobin in red corpuscles in lungs and the heart pumps the blood with these corpuscles into the whole body.

In tissues and cells the oxygen O2 from blood is consumed and carbon dioxide CO2 and waste substances are transferred into blood. Blood transports CO2  from tissues and it is breathed out from the body by lungs.

The volume of air breathed out after a maximum breathing in is called vital capacity . Vital capacity of an adult is about 3-5 dm3.

The following chart represents dependence of air volume in lungs by relaxed breathing and by maximum breathing on time.

 

 

This chart clearly shows various volums of lungs.VT is the air volume that man breathes in and out in relaxed phase. The big curved line represents the vital capacity, i. e. the maximum breathing in and afterwards the maximum breathing out. The expiration spare volume signifies the quantity of air that can still be breathed out after a relaxed inhalation. The residual volume is the air volume that remains in lungs after the maximum expiration. The total vital capacity is the air quantity that is contained in lungs after maximum inhalation.


Aids:

Glass vat, graduated measuring vessel, rubber tube with glass tube.


Procedure:

1.

Pour water into about two thirds of glass vat.

2.

Fill in a larger measuring vessel with water and cover it with paper that is pressed to the vessel. Turn the vessel with water and paper upside down and put it into the vat so that no water runs from the vessel out.

3.

Prepare a rubber tube on the end of which there is a bent glass tube.

4.

Breath deeply in and breath the air out into the vessel with water by means of the tube.

5.

Observe the air pushing the water out of the vessel into the glass vat.

6.

Establish the volume of expired air on the scale of the vessel.

7.

Every pupil in the group carries the experiment twice out under different conditions (deep and relaxed breath, after warming up etc.).Observe how the measured dates change in dependence on physical activity).

8.

Compare the air volume in the lungs of your schoolmates by means of a bare chart (the height of the column is directly proportional to the air volume).


Table:

Student

Vital capacity [dm3]

Jiri

3.4

Lubos

3.6

Vojtech

3.6

Karel

3.4


Picture:


Chart:


Computation:

1.

The mass fraction wA  of the original dry soup mixture in the whole suspension of goulash soup:

2.

The mass fraction wB of the solid (in water insoluable) part in the original dry soup mixture in the bag:

3.

The mass fraction wC of the solid component in the ready soup:


Conclusion:

Vojtech together with Lubos have got the biggest vital capacity 3.6 dm3. Jiri has got 3.4 dm3 vital capacity and Karel has got the smallest vital capacity 3.3 dm3. Vital capacity depends on fitness of the individual. It is good to know one´s vital capacity for physically demanding sports, e. g. for diving.