What is the general capacity of the household thermos?

The volume of ordinary household thermos (thermos, hot water kettle) is divided into two kinds of sizes:

1. The smaller one is a 4-pound bottle, which is actually filled with about 2,000 ml of water;

2. The larger one is 8 pounds, which is actually filled with about 3,700 ml of water.

Expanded Information:

The hot water kettle, also known as the The hot water bottle, also known as a thermos flask, was invented by Dewar, a scientist from England, who first made compressed hydrogen gas into a liquid, known as liquid hydrogen, in 1900. This had to be bottled, but there was no such thermos at the time. So he developed his own. He used a vacuum, i.e., he made a double-layered bottle and pumped the air out of the compartment to cut off conduction.

The modern thermos flask was invented in 1892 by British physicist Sir James Dewar. At that time he was carrying out a gas liquefaction research work, the gas to liquefy at low temperatures, the first need to design a gas and the outside temperature can be isolated container, so he asked the glass technician Burger blew for him a double glass containers, two layers of the inner wall coated with mercury, and then pumped off the two layers of the air between the formation of a vacuum. This vacuum bottle is also called "Du bottle", can make the liquid contained in it, regardless of cold, hot temperature is maintained for a certain period of time.

Reference:

Baidu Encyclopedia-Hot Kettle