the correct answer is thermal or light
Answer:
What? i think its an incomplete question
Explanation:
Atomic number = protons
Protons = P Electrons = E P = E
Atomic mass = Neutrons + Protons
Atomic number = atomic mass = neutrons
P = E
AM - AN = N
Example:
Calcium = 20 Protons 20P = 20E
Atomic mass - atomic number = neutrons :)
Group 18 are stable because thier outermost shell ocuppied with full of electrons and its chemically inert
Answer:
the answer is d which is soap solution because it's a soap solution that can measure the degree of hardness of a water if the water forms with this soap solution then the water is hard but if the water forms foam with soap then it is soft