The first subatomic particle discovered by scientists was the negatively charged electron. Why did scientists conclude that the atom also contained positively charged particles?

The element is characterized by its $"atomic number, Z"$, where $Z$ is the number of nuclear protons, which are massive, positively charged particles. Now we were given the number of...

These are extremely small bodies that orbit the nucleus in "orbitals" and are one of the main foci of quantum mechanics.

And the number of protons in the nucleus defines $Z$, the , which specifies the identity of the element. I have written before that the sign of the charge of...

Protons are massive, positively charged nuclear particles. The number of protons gives $Z$, the , which defines the identity of the element. Neutrons are massive, neutrally charged nuclear particles. A...

The most common subatomic particles are protons, neutrons, and electrons. Protons are positively charged and reside in the nucleus, along with neutrons which have no charge. These particles are...

And announce that I have discovered $"antimatter"$. The proposition you are making is hard to rationalize. What's an atom? As far as anyone knows, it's a collection of fundamental particles,...

If it is a neutral atom (and we must assume so), for every electron there must be a positively charged nuclear proton. Thus $Z," the atomic number = 30"$. And...

You might have to rethink this question. All states of matter, $"solids, liquids, and gases,"$ are composed of atoms, which in turn are composed of positively and neutrally charged, massive...

For the lithium atom, $Z=3$; there are 3 positive, nuclear charges. There are 3 extra-nuclear electronic charges, i.e. borne by the 3 electrons, in the neutral atom. Lithium generally loses...

Protons, massive, positively charged nuclear particles, have an opposite electronic charge to electrons, extra-nuclear particles of negligible mass. The positive/negative charge convention is entirely arbitrary. The point is that...