the base constructive structure of a matter

combination with two or more matter

charged particles

+1

+2

-1

-2

-

+

mole is atom of the same elments with the same nombor of proton and electron but different number of neutron

Mole is a base unit of mesaure of quantity of a substance

non of this above

Because the heat energy use to overcome the force of attraction between particle naphtalene

Because the heat enery loss to surrounding is balenced by the heat energy that released when the bond form

MgO

Mg2O

Mg3O2

MgO3

32

16

18

21

2-

+

-

2+