Both the pebble and metal bead of the same mass will be equally accelerated if they are at the same place, in this case, they are in the same place meaning they will be accelerated at the same speed towards the earth. Thus even if they are in the water they will sink at the same speed and finally will reach the bottom of the cup.
A solid metal bead of the same size is dropped into the same cup and sinks to the bottom of the cup. How do the pebble and the metal bead compare? They both have the same mass. They are both denser than water.
A pair of elements will most likely form an ionic bond if one is a metal and one is a nonmetal. These types of ionic compounds are composed of monatomic cations and anions. ( K, Cl)...
