Because they are highly reactive with many other elements.
Alkali metals, such as sodium and potassium, are so reactive that they are never found as uncombined elements in nature. They readily react with other elements to form compounds.
Group 1 and group 2 metals
Fluorine is never found in nature as a pure native element due to its high reactivity. It typically forms compounds with other elements such as in minerals like fluorite.
Fluorine is an element that is never found in its free state in nature due to its high reactivity, forming compounds with other elements very quickly.
Noble gases or group 18 elements
group 1 elements
Alkali metals, such as sodium and potassium, are so reactive that they are never found as uncombined elements in nature. They readily react with other elements to form compounds.
The group you're thinking of is group 1, the alkali metals. They include sodium and potassium, and you're right, they are so reactive that they do not exist by themselves. They only exist in compounds with other elements.
Group 1 (alkali metals) and Group 17 (halogens) in the periodic table contain elements that are highly reactive and are never found in their free state in nature. Alkali metals readily react with water or air, while halogens are highly reactive nonmetals that form compounds with other elements quickly.
Fluorine and francium are two elements that are never found as elements in nature due to their high reactivity. Fluorine readily reacts with almost all elements, while francium is extremely radioactive and decays quickly into other elements.
because they are too reactive to exist on their own, they bond with other elements in nature to satisfy their need for electrons
Group 1 and group 2 metals
The alkali metals (Group 1 elements) such as sodium, potassium, and lithium occur only as compounds in nature because they are highly reactive and readily form compounds with other elements or molecules. They are never found in their pure elemental form in nature.
Fluorine is never found in nature as a pure native element due to its high reactivity. It typically forms compounds with other elements such as in minerals like fluorite.
Fluorine is an element that is never found in its free state in nature due to its high reactivity, forming compounds with other elements very quickly.
Noble gases or group 18 elements
They're too reactive. They will react with oxygen or moisture in the air, so they can't exist as pure elements unless protected. The usual method is to submerse them in oil.