Global Science

The Elements: Volume 1 - A closer look at SODIUM


Could you live without it? Na...

Welcome to the first installment of Global Science’s new section: The Elements! Today, you will learn about one of the most important elements in our world, SODIUM!

If you’re anything like our reporters over here, maybe when you were younger, you've asked to pass the sodium at the dining table, to sound all smart and fancy. However, sodium, the element, is much more than its usage in salt. Read on to find out more.

A Little History: It's Discovery

In 1807, a chemist, by the name of Humphry Davy, who had discovered many of the alkali metals, discovered sodium. Not being naturally discovered in nature, sodium was, however, recognized in compounds. Davy took one of it's compounds, sodium hydroxide, and isolated sodium from it using electrolysis.

Blast Off: The Basics

Sodium is a metal represented by the symbol "Na". From the Bohr-Rutherford diagram, we can tell it has 11 protons and 11 electrons. With an atomic number of 11 and atomic mass of 23, sodium also has 12 neutrons.

It is located with wonderful group 1, the Akali metals. Being on row 3, sodium has 3 electron shells. 11 electrons being split over 3 shells means one valence electron on the last shell. From this we can already tell that sodium must be a very reactive element who's always trying to lose that one electron to be balanced. On top of that, this cool element is a metal and solid at room temperature. RAD!

Judging Elements By Their Cover: Physical Properties

Now that we've covered the basics, let's check out what physical properties sodium has.

  • Color: silver-grey
  • Phase: solid
  • Density: 0.968g/cm^3
  • Melting point: 97.72 degrees Celsius
  • Boiling point: 883 degrees Celsius
  • Malleability: high
  • Ductility: easily pulled and stretched
  • Luster: shiny
  • Conductivity: can conduct heat and electricity well
  • Hardness: very soft, can be cut with a knife

Friends and Reactions: Chemical Properties

Sodium reacts with other elements to create some of the most useful elements in the world. Being a very reactive element, sodium can't even be stored by itself because of it's reaction to air! Instead, it is often kept in oil to prevent any reactions. Here are some of it's reactions:

  • Reacts explosively with water, creating sodium hydroxide and hydrogen gas. When the reaction occurs, heat is produced and ignites the hydrogen gas, causing a fire.
  • Reacts with oxygen and forms sodium oxide instantly.
  • Reacts with the halogen family to create ionic salts. An example would be chlorine and sodium forming sodium chloride, what we know as table salt.
  • Is flammable, and burns a yellow-gold flame

Where Is It Found?

Sodium, the element, is never found pure in nature, due to being such a reactive element. It instead is found in a variety of mineral, namely all the compounds it creates. Some minerals it is found in include table salt, amphibole,cryolite, soda niter, and zeolite. And while not found pure, sodium in it's compound forms is the 6th most abundant element in the earths crust. Not only that, but sodium is also found in STARS!

So How Does This Tie In With You Today?

So you know sodium's important, but why? What do we use sodium for? Biologically, humans and animals can't survive without sodium. Our bodies need it to function our nervous system and brain. Humans need an intake of 1.5g a day, but digesting too much sodium can lead to health problems just as too little would. In fact, many people already get enough sodium from their diet, so don't go scheduling sodium into your nutrition tracker! (

Other uses for sodium include creating a yellow glow in street lamps and exchanging heat in some nuclear reactors. This element is also very useful in the kitchen, Sodium chloride, table salt, is used to season almost all our meals. It is also used to cure many foods, preserving meats for long amounts of time. Sodium Bicarbonate, otherwise know as baking soda, is important as a leavening agent in baked goods.

Try to imagine a world with no salt, or preserved meat. Yeah, that's how important sodium is! Next time you eat anything, think about the salt in it and what it does for your body.

Common Compounds:

  • NaCl (sodium chloride)
  • NaOH (sodium hydroxide)
  • NaSO (sodium sulfate)
  • NaNO (sodium nitrite)
  • NaF (sodium fluoride)
  • NaCO (sodium carbonate)

Affecting Our World

Sodium, being very reactive, can explode in water and contaminate the water. In liquid form, sodium hydroxide leaks into soil, again contaminating water sources. Furthermore, sodium chloride, road salt, has been discovered to be a threat to our environment. Imagine the damage salt can do on a normal sidewalk, and park, leaking into the sewers and dehydrating grass. However sodium is also needed for animal's and plant's nutritional needs, therefore helping our environment and ecosystems.