It would go mouldy because of the bacteria already present on it, however if you somehow disinfected the bread while it was in the container, it would not go mouldy, it would simply go dry and hard as rock. The only real way you could do this is by heating it up to 180+ degrees C while in the container.
the air in the container expands
yes as long as it wrapped in cling film or in an air tight container.
Put the cookies in an air-tight container. A Tupperware like container with sealed lid works well. Put a piece of bread into the container. The cookies absorb the moisture out of the bread. in a few days, the bread wil be hard and dry, replace with a new piece. Try it - it really works!
it will go moldy its true i did it once !
Toasted bread can be conserved or preserved by grating or grinding it into fine bread crumbs. Completely dry crumbs can be stored in an air tight container at room temperature or in the freezer for several months.
Then your container was not airtight.
I store mine in an airtight container on a shelf in my pantry or in a drawer. As long as it's airtight, it will stay soft. In and airtight container. If it gets hard, put in a plastic bag with a slice of bread. This will help soften it up.
The hermetic refers to being air tight. The term commonly used is hermetically sealed. An example of a hermetic container would we a glass jar, or any container with an air tight seal.
If bread that is already baked is frozen the life of the bread is about a month in the freezer. Bread tends to lose moisture when it is frozen. Bread dough that is frozen will last 6 months or more in the freezer if it is placed in an airtight container.
a sealed container or air tight clingfilm
That just refers to a seal that is gas (air, specifically) tight.
Once cookies are baked and cooled, they should be stored in an air-tight container. Placing a piece of soft bread or an apple slice in the container with the cookies will keep them soft and moist. Take care that the apple slice does not directly touch any cookies; it can be placed in a tea egg or some other permeable small container.