5 elements make the world-fire, water, earth, air, and Space. These five elements are responsible for making this world. If we talk about the elements discovered by the scientists that exist on earth, we will see as they were discovered, they were arranged in a periodic table. Alkali and alkaline earth metals are two of the parts in which the periodic table is made. But they’re different from each other.
Alkali vs Alkaline
The main difference between alkali and alkaline is that alkali is the group 1 metal of the periodic table such as potassium, lithium, sodium, rubidium, caesium, whereas the Alkaline earth metal is the group 2 of the periodic table with elements such as beryllium, barium, hydrogen, strontium, magnesium, radium, calcium, etc. Alkali metals are some, while the alkaline elements are harder.
The alkali metals are group 1 of the periodic table. Elements like sodium, lithium, caesium have an extra electron in their valence shell. The compounds they form with other elements are caller alkali compounds. Like NaCl, where Na is sodium and Cl is chloride, and they together form a bond, and that Compound will be known as alkali compounds.
The Alkaline earth metal makes group 2 of the periodic table. Elements like calcium, magnesium also makes hydroxide ions when added to water. Also, If we talk about the pH value, Alkaline earth metal has higher pH values. We can simply denote with >7 for a better understanding.
Comparison Table Between Alkali and Alkaline
|Parameters of Comparison||Alkali||Alkaline|
|Definition||In the periodic table, Alkali metals are the group 1 elements.||Alkaline is the group 2 elements of the periodic table.|
|Elements||Some elements like sodium, lithium, caesium, potassium, are alkali metals.||Elements like calcium, magnesium, rubidium, are alkaline earth metal.|
|Valence electrons||In alkali metals, the last valence shell has one electron.||In alkaline metals, the last shell has two electrons.|
|Formation||Alkali metals form +1 cations.||Alkaline forms +2 cations.|
|Ionisation energy||If we talk about elements in group 1, the ionisation energy is low.||Alkaline has higher ionisation energy.|
What is Alkali?
Our world is made up of elements. Some exist in sharing electrons to someone making ionic bonds, and some make covalent bonds fulfilling each other’s octet. However, some things are common. The bonds they form are always in a stable state. And all elements strive to make bonds with someone to find stability.
Alkali metals are the group 1 elements of the periodic table designed by scientists. There were various periodic tables suggested, but in 1913, the final table was considered one of the most reliable and appropriate ones. Alkali metals like lithium, sodium, potassium, caesium, etc., have one thing in common. They have one election in their last shell.
This electron plays an important role in stabilising the elements. Their last electron can be used to make bonds with those elements which have 7 electrons in their last shell and need one more. Like chlorine, If we see its last shell, it’s Deficit by one electron. This sodium electron can be given to chlorine to form bonds making sodium chloride.
The final stability comes when your last shell is complete. Either accept from someone or give someone. The last shell must be full to be stable. Alkali metals have a pH of 7 and more which in turn turns the red litmus paper into blue, showing acidity property. Also, alkali metals can be used to naturalize acidic reactions. These have less ionisation energy since it’s easy for them to donate one electron from their valence shell.
What is Alkaline?
The periodic table suggested in 1913 classifies elements based on their nature. You’ll see some groups that need one electron, some will need two, and some are full as well. Group 1 is Alkali metals which tends to donate one electron to reach a stable state.
Alkaline earth metals are generally those elements that tend to give two electrons to these elements that need exactly two elements. Elements like calcium, beryllium, magnesium have two electrons in their valence shell which they can donate to those who need two elements.
If we see a compound, CaO, which is known as calcium oxide. Here we can see oxygen has 6 electrons in its valence shell and needs two more to complete its octet. However, at the same time, the calcium has 2 electrons in his valence shell and needs to donate two to stabilize himself. So they come together to form a bond that is in favour of both stabilizing each other.
Alkaline earth metals have a pH of more than 7 turning red litmus paper into the blue. Alkaline earth metals form +2 cations, and this positive sign indicates that the donation of two electrons has performed. Also, alkaline metals have high ionisation energy because it’s easy to donate one electron, but a donation of a second electron takes lots of energy.
Main Differences Between Alkali and Alkaline
- The alkali metals have less ionisation energy, while the Alkaline metals have high ionisation energy.
- The alkali metals are soft by nature, while the Alkaline metals are hard since they’re found on earth.
- Alkali metals have a larger atomic radius, while Alkaline metals have a low atomic radius.
- Alkali metals have one extra electron in their valence shell, while alkaline metals have 2 extra electrons.
- Alkali metals like lithium, sodium, potassium and Alkaline metals like calcium, beryllium, magnesium.
Whether an element gives electrons or accepts them, the destination remains the same. To find stability either by donation or by forming covalent bonds. The periodic table is all about those elements that have extra electrons, deficiency of electrons, and those that have a full octet.
Full octet elements are those which doesn’t react with anyone and are already stable. Examples like helium, argon, xenon have complete octets and don’t require any electron. And we can say their ionisation energy is very high among all the elements since it’s very tough to pull out electrons from the last shell.