Simply put, 4 liters of water is 8 pounds of water. L is the unit of capacity, and 4-liter kettle is the theoretical calculation value, with certain error. Another factor is the physical change of water expanding with heat and contracting with cold. So let it go. It's short, not too full, less than 4 liters of water. Because the capacity of one liter is one kilogram, it is two kilograms when converted into municipal units, and four liters of water is eight kilograms.

The kettle is made of various materials, such as stainless steel, plastic, glass, resin, etc. And special materials such as birch bark appearance and high-tech plastic liner.

Descaling method:

Chop a lemon and boil it in a pot. After soaking for a period of time, the scale is easy to remove. Supermarkets also have special detergent, the main ingredient of which is citric acid, which has the same effect as lemon.

In a new kettle, put more than half a pot of sweet potato, fill it with water, cook the sweet potato, and then boil the water, so that scale will not accumulate. However, it should be noted that do not scrub the inner wall of the kettle after cooking the sweet potato, otherwise it will lose the descaling effect. For the old kettle that has been covered with scale, after being boiled once or twice by the above method, not only the original scale will gradually fall off, but also it can prevent the scale from accumulating again.

When boiling water in an aluminum pot with scale, add 1 teaspoon baking soda and boil for a few minutes, and the scale will be removed.

It is difficult to remove the pot that boils water after a long time. If you use it to cook eggs twice, you will get the ideal effect.

Put an empty kettle on the stove to dry the water in the scale. When the bottom of the kettle cracks or bursts, take it off and fill it with cold water quickly, or wrap the handle and spout with a rag and hold it with your hands. Sit the dried kettle in cold water quickly (don't let the water fill the kettle). Repeat for 2 to 3 times, and the scale at the bottom of the pot will fall off due to thermal expansion and cold contraction.

If the kettle has scale, you can put a few even vinegar in the water and burn it for an hour or two, and the scale will be removed. If the main component of the scale is calcium sulfate, the soda solution can be poured into the kettle for cooking to remove the scale.