If we inflate a balloon in the summer and we leave it in the sun, the balloon explotes in contrast, if we inflate it in the winter and we leave it in the same place ,it losses volume why does this happen?

The summer sun increases the temperature and hence volume of air in the balloon resulting in the balloon bursting. On the other hand, the winter cold decreases the temperature and hence volume of air in the balloon resulting in the balloon shrinking.

Explanation:

According to the Charles' gas law, an increase in temperature at constant pressure is proportional to volume.

Also, according to Gay-lussac's law, an increase in temperature at constant volume is proportional to pressure.

When thr inflated balloon is left in the summer sun, the temperature of the gas in the balloon increases and so does the pressure. This increase in pressure will only be relieved by expansion of the balloon which eventually results in it bursting.

In the winter on the hand, the temperature of air in the balloon decreases and so does the pressure of the gas. Therefore, the volume of the gas in the balloon will become smaller and the balloon will shrink in size.