Which of the following statements about alkali metals is true?

alkali metals have full valence shells

alkali metals form 1- cations

alkali metals are very reactive

alkali metals form 2- cations

OPTION C, Alkali metals are more reactive.

Explanation:

Since alkali or IA group elements are more electropositive and they readily loose Electrons to form monocation. Hence they are very reactive.

Their valency shell configuration is ns1, incomplete.

They forms only monocations like Na+, K+ etc

Alkaline earth metals forms +2 ions

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance