How many liters is an ordinary thermos?

Ordinary thermos, the smaller one is a 4 kg bottle, and the actual water content is about 2000ml (about 2.27 liters); 8 kg, the actual water volume is about 3700ml (about 3.63 liters).

The function of a thermos bottle is to keep the temperature of hot water in the bottle and cut off the heat exchange inside and outside the bottle, so that the "heat" inside the bottle can't get out and the "cold" outside the bottle can't get in.

If you put the popsicle in a thermos, the "heat" outside will not easily run into the bottle, and the popsicle will not easily melt. Therefore, it is scientific to call a thermos bottle a thermos bottle, because it can keep both "hot" and "cold".

Extended data

The weakness of heat preservation of thermos bottle is that the bottle mouth has heat conduction at the joint between glass bottle mouth and glass bottle mouth. Bottle mouth usually relies on cork or plastic plug to stop heat loss, so the larger the capacity of thermos bottle, the smaller the bottle mouth and the higher the heat preservation efficiency.

It is very important to maintain the high vacuum of bottle wall interlayer for a long time. If the interlayer expands gradually or the sealed exhaust tail is destroyed, the vacuum state of the interlayer is destroyed, and the thermal insulation efficiency of the thermos bottle liner will be lost.

In addition to glass, thermos bottles are made of stainless steel or non-toxic and tasteless plastic. Metal bottle liner is durable and not easy to be damaged, but its thermal conductivity is much higher than that of glass, and its thermal insulation efficiency is slightly poor.

Single-layer or double-wall containers made of plastic are filled with foamed plastic for thermal insulation, which is light and convenient and not easy to break, but the thermal insulation efficiency is worse than that of thermos bottles.