Because if they are submerged in the solvent, they would dissolve! This would prevent them from seperating and not allow you to actually record anything
Answer:
Both are highly reactive.
Explanation:
A has 1 valence electron D has 3
A is sodium D is aluminum
BY CHECKING THE REACTIVITY OF AN ELEMENT WHICH IS MOST REACTIVE OR NOT AND YOU STUDY TYPE OF CHEMICAL REACTION IN 1 CH AND YOU CHECK THE REACTIVITY OF ELEMENTS IN 3 CH METALS AND NON METALS PAGE NO 45 IN NCERT BOOK