It’s a soft metal, reactive and with a low melting point, with a relative density of 0,97 at 20ºC (68ºF). From the commercial point of view, sodium is the most important of all the alkaline metals. Sodium reacts quickly with water, and also with snow and ice, to produce sodium hydroxide and hydrogen.

Sodium is a soft, silvery metal that reacts very vigorously with water, and tarnishes easily in air. It is the fourth most abundant element in the Earth’s crust, which consists of 2.6% sodium by weight; seawater is about 1.5% sodium.

Physical properties Sodium is a silvery-white metal with a waxy appearance. It is soft enough to be cut with a knife. The surface is bright and shiny when first cut, but quickly becomes dull as sodium reacts with oxygen in the air. A thin film of sodium oxide (Na 2 O) forms that hides the metal itself.

Know Your Numbers Americans eat on average about 3,400 mg of sodium per day. However, the Dietary Guidelines for Americans recommends adults limit sodium intake to less than 2,300 mg per day—that’s equal to about 1 teaspoon of table salt!

But too much sodium in the diet can lead to high blood pressure, heart disease, and stroke. It can also cause calcium losses, some of which may be pulled from bone. Most Americans consume at least 1.5 teaspoons of salt per day, or about 3400 mg of sodium, which contains far more than our bodies need.

What does the urinary system do? Your urinary system filters your blood to get rid of what your body doesn’t need. It eliminates extra water and salt, toxins, and other waste products.

The body loses water primarily by excreting it in urine from the kidneys. Depending on the body’s needs, the kidneys may excrete less than a pint or up to several gallons (about half a liter to over 10 liters) of urine a day.