The bracket just separate an atom or the ion and in the above it means there are two hydroxide molecules
so bracket function is just to separate ions and molecules
hope it helps
Answer:
The "right" answer is 4. When matter is a gas, the particles flow freely, having no fixed shape or volume and contain a lot of extra space between particles.
However the last part, "...with a lot of empty space between them giving it energy" is (I'm fairly certain) incorrect. The relationship is the other way. Energy is added to the system, causing the particles to move more, thus building up the space between them.
Heterogenous mixtures can separates due to differences in size of components
Neon is a noble gas, so is very stable and has an atomic number of 10. So it has 10 protons and 10 neutons. So no it does not need to bond.
