In this video excerpt native NOVA"s "Hunting the Elements," New York Times technology columnist David Pogue investigates chemical reactions including sodium. Uncover out just how the electron configuration of sodium, one alkali metal, makes it a very reactive element. Fulfill chemist and author Theo Gray, that demonstrates 2 sodium reactions: a spectacular explosive reaction v water; and also an exciting reaction v chlorine, a very reactive halogen. Examine just how sodium and chlorine atoms incorporate to kind the compound salt chloride (ordinary table salt).

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VIEWMedia Type: VideoRunning Time: 3m 22sSize: 12.1 MBLevel: qualities 6-12

Source: NOVA: "Hunting the Elements"

This media asset was excerpted indigenous NOVA: "Hunting the Elements."

Teaching Tips

Here are some of the main concepts students need to take far from this video:

Sodium (Na) is an alkali metal; it is shiny and also soft v a single electron in that is outermost shell.Alkali metals are extremely reactive due to the fact that they readily lose their outermost electron. Salt combines v water in one explosive reaction.Chlorine (Cl) is a halogen; that is a very reactive element that easily gains one electron to fill its outermost shell.Sodium and also chlorine, two highly reactive elements, incorporate to form the stable compound sodium chloride (ordinary table salt).

Questions for Discussion

Describe the electron configuration of sodium.Why is sodium highly reactive?How deserve to two turbulent elements, such together sodium and chlorine, integrate to do a stable compound?


DAVID POGUE (Technology Guru): Sodium: price Na; 11 protons and also 11 electrons i ordered it in shells together two, eight and also one. Salt is an alkali metal. Like all the elements in this group, it"s no hope to get rid of that extra electron.

THEO GRAY (Chemist and Author): If you reduced it quickly,…

DAVID POGUE: I should see some silvery…

THEO GRAY: …you need to see a silvery surface inside.

DAVID POGUE: Indeed. Wow.

It slices like cheese, but it"s in reality a soft metal.

Theo"s available to put on among his favorite sodium demonstrations. What happens when the pure element dumps its outer electron in a violent altercation with simple water?

He insists us wait until nightfall, once the reaction will certainly be many spectacular.

Kids, perform not shot this in ~ home!

The totality purpose of this contraption is just to dump it right into the bucket that water?

THEO GRAY: Yeah. This is a, it"s a sodium dumping machine.

DAVID POGUE: all right, let"s give this a try. Below we go!

Nice! Oh!

What we"re seeing is what happens as soon as sodium"s extra electron tears apart water molecules, release flammable hydrogen gas—the H in H2O—which explodes once it mixes with air.

The following day, Theo takes it increase a notch. As if salt plus water weren"t violent enough, now he desires to combine the exact same deadly salt with an additional lethal element: chlorine, one of the halogens.

The result, that claims, will be a tasty flavoring because that a net full of popcorn.

Isn"t chlorine fatal poison?

THEO GRAY: Absolutely.

I mean, chlorine, chlorine—they used it as a toxicity gas in human being War I.

DAVID POGUE: It"ll be perfect safe once these two deadly ingredients combine?

THEO GRAY: ns didn"t say that. I claimed that after they"re combined, the an outcome is perfect safe. The actual procedure of combine them is fraught with difficulties.

DAVID POGUE: Okay. And also that"s why we"re pull up prefer miners here.

First, a hunk of salt in a dry metal bowl,then a jet the pure chlorine: surprisingly, no explosion.

Somehow, when these two bad boys that the routine table come together, they calm down.

At the atomic level, sodium, an alkali metal, had actually an electron that didn"t want, and chlorine, a halogen, desires desperately come grab one electron. When the handoff to be complete, both atoms wound up with complete shells, making castle stable and able to sign up with together to type a decision compound we can"t live without: salt chloride, table salt.

Now, ns don"t precisely see, like, a heap of salt anywhere.

THEO GRAY: No, the salt, most of the went increase in the smoke. That is, the went in the popcorn.

DAVID POGUE: that tastes like salt, the an excellent stuff, fresh.

THEO GRAY: fresh salt.

DAVID POGUE: just the freshest salt in ~ Theo"s farm.

See more: Is Cos An Even Or Odd Function S Odd Or Even? Even And Odd Functions

Theo"s backyard reactions have offered me a crucial insight: how aspects come with each other to form compounds is all about electrons.