Burning alcohol vapor Let's imagine a plastic container, sealed closed. We fill half of it with alcohol, then we generate a spark.
The question is: can the mixture of alcohol and air burn, or do we need a hole to let air in/out?
 A: 'Homework' answer - depending on the amount of air and the temperature the alcohol-air may form a ratio of alcohol-oxygen that will burn until all the oxygen is consumed.
'real world' - the spark might set fire to the plastic, the alcohol may get hot and spray out of the electrode hole as a flame-thrower. = Don't try this at home. 
A: 
The question is: does the
  air+alcohol-gas burn creating a big
  pressure or does the container need of
  a little hole to burn?

Strange "need of a little hole", What does that mean? 

The question was: do we need of hole
  to start the ratio of oxygen+alcohol

Another time strange "need of hole". And on the whole two rather different questions.
One thing I can say: In a container with alcohol vapor (I assume ethyl alcohol is meant) 
and air one will have 


*

*40 mmHg partial pressure of ethanol at 19 °C

*720 mmHg partial pressure of air  
This makes 40/760 = 5.3  vol-% of ethanol. 
A view in tables says that ethanol has 
Lower explosive limit (LEL) 3.3 vol% 
Upper explosive limit (UEL) 19 vol% 
Answer is: Your container will explode, the liquid ethanol 
will be sprayed around, burning. I'd prefer to be several
dozens of meters away from such "experiments", at least. 
