protons and electrons are both always the atomic number which is 9 in this case.
For neutrons you subtract the atomic number (9) from the weight of the atom (18.998) some teachers will want you to round to the nearest whole (19). We do this because the number of protons is the atomic number so if you subtract the protons from the whole weight of the atom you would have the electrons and neutrons left. Since electrons weigh so little we don't have to subtract them. Weighing neutrons and electrons would be like weighing an elephant (neutrons) and then putting one marshmallow on the scale (electron).
I think the correct answer from the choices listed above is the first option. The Greeks were the first to use the term atom. In 450 BCE, Democritus coined the term átomos which means "uncuttable" or "the smallest indivisible particle of matter".
Answer:
B
Explanation:
It's the same substance but in different states.
HETEROGENEOUS mixtures contain substances that are
not uniform in composition. The parts in the mixture can be separated by physical means.
