You more than likely think that water as a problem that deserve to put the end fires. But some elements are so reactive that they burn in water. In fact, they virtually explode in water. An example is shownin the photograph below. About 3 pounds of sodium were added to water, and also the result was an explosive reaction. Why is sodium such a reactive element? In this section, girlfriend will uncover out.

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Figure (PageIndex1): sodium reacting v water.

The very first Group

Sodium (left( ceNa ight)) is an element in group 1 the the regular table the the elements. This team (column) of the table is displayed below. It has the nonmetal hydrogen (left( ceH ight)) and six metals dubbed alkali metals. Aspects in the same group of the periodic table have actually the same variety of valence electrons. These space the electrons in the outer energy level the the atom that have the right to be affiliated in gaianation.netistry reactions. Valence electrons determine many of the properties of one element, so aspects in the same group have similar properties. Every the elements in team 1 have just one valence electron. This renders them an extremely reactive.

Figure (PageIndex2): team 1 of the periodic table.

Reactivity of team 1 Elements

Hydrogen is a very reactive gas, and the alkali metals are even much more reactive. In fact, they room the most reactive metals and, along with the facets in team 17, space the most reactive of all elements. The reactivity that alkali metals increases from the top to the bottom the the group, for this reason lithium (left( ceLi ight)) is the least reactive alkali metal and also francium (left( ceFr ight)) is the many reactive. Because alkali steels are therefore reactive, they are discovered in nature only in mix with various other elements. Castle often incorporate with group 17 elements, i beg your pardon are very "eager" to gain an electron.

Other nature of Alkali Metals

Besides being really reactive, alkali steels share a number of other properties:

Alkali metals are every solids at room temperature. Alkali steels are short in density, and some of lock float ~ above water. Alkali metals are fairly soft. Some are also soft sufficient to reduced with a knife, prefer the sodium pictured in the figure below.

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api/deki/files/78133/CK12_Screenshot_6-9-4.png?revision=1&size=bestfit&width=406&height=238" />Figure (PageIndex4): Hydrogen has actually the smallest, lightest atom of all elements. Pure hydrogen is a colorless, odorless, tasteless gas the is nontoxic yet highly flammable. Hydrogen gas exists greatly as diatomic ("two-atom") molecules (left( ceH_2 ight)), as shown above. Hydrogen is the many abundant facet in the universe and also the 3rd most abundant facet on Earth, and also occurs mostly in link such together water.what group on the periodic table is the most reactive