What makes atoms chemically reactive

Due to the laws of quantum chemistry, electrons occur in pairs whenever possible. Alkali metals always have one odd electron furthest from the nucleus.

It is the electron involved in chemical reactivity. The outermost electron is held less tightly and escapes more readily. Therefore, the alkali metal with the higher number is more chemically reactive.

This makes francium the most reactive of the alkali metals. He furthered his education through the University of Virginia's Citizen Scholar Program program, taking many courses in organic and quantum chemistry.

Either it can share electrons with a neighbouring atom to form a covalent bond or it can remove electrons from another atom to form an ionic bond.

To form an ionic bond, a halogen atom can remove an electron from another atom in order to form an anion e. To form a covalent bond, one electron from the halogen and one electron from another atom form a shared pair e.

Within each group of nonmetals, reactivity decreases from top to bottom, because the valence electrons are at progressively higher energies and the atoms do not gain much stability by gaining electrons. In fact, oxygen the lightest element in Group 16 is more reactive than chlorine, even though it is not a halogen, because the valence electrons of oxygen are closer to the nucleus.

Therefore, a metal from the bottom of Group 1 like potassium and a nonmetal from the top of Group 17 like fluorine will react violently, because they both benefit greatly from the reaction.

How do valence electrons determine chemical reactivity? Ernest Z. Jan 7, Explanation: The number of electrons in an atom's outermost valence shell governs its bonding behaviour. And reactivity is a shell game. Imagine that these balls are electrons, and the target is an atom. Electrons don't just pile on around the nucleus. As with skee-ball, where you land, relative to the center counts.

The electrons take up positions in what can be thought of as concentric shells. The first shell maxes out at just two electrons, the next holds eight, then it goes up to eighteen. An atom with eight electrons in its outer shell makes one happy, satisfied atom. They are called the halogens.

They have an outer shell that needs just one more electron to be full. And they'll grab it any way they can. The group includes fluorine and bromine, but the most notorious is chlorine: 17 protons surrounded by 17 electrons, arranged in three shells of two, eight and seven, one short of being full.

It's that extra electron chlorine will get any way it can, sometimes with violent results. That's why chlorine gas was used as a deadly poison in World War One.

This will take electrons from kittens. It'll go and steal an electron from off the water in your lungs and turn it to hydrochloric acid, because it really wants an electron. Each of them has full shells, plus one extra electron sitting in a new, outer shell.