Differences between Atom, Element, Molecule, and Compound
Atom vs Element vs Molecule vs Compound: Clear comparison of these key chemistry terms, with examples

In chemistry, intermolecular interactions are molecular interactions between neighbouring molecules, governed by attractive and repulsive forces.

An acid is like a sour superhero, let’s call him Acidus, that loves to give away tiny pieces called protons (or H⁺ pieces). The stronger he is, the more protons he can donate as H+. This increased concentration of H+ ions in water makes a solution acidic.

A great experiment to demonstrate the existence of atoms is Brownian motion, originally observed by Robert Brown in 1827.
Here’s how the curious chemist in you can try it: