1)Alkali metal with smallest atom.
Answer:
Lithium (Li)
2) The most abundant element in the universe.
Answer:
Hydrogen (H)
3)Radioactive alkali metal.
Answer:
Francium (Fr)
4)Ions having high concentration in cell sap.
Answer:
Potassium ions (K+)
5)A compound having hydrogen, aluminium and lithium as its constituent elements.
Answer:
Lithium aluminium hydride (LiAlH4)