You are asking for comparatives. Each state can be any when compared to another state except the extremes. Liquid or gas either lower or higher depending on what you compare it to.
This is a solid.
This is a liquid.
It's not necessary. If a compound has high optical density, it means that it absorbs more light at the given wavelength than some reference compound. There is no simple relation between density of matter and optical density. Even more I am pretty sure you can find a lot of compounds with lower densities (of matter) but having high optical density.
Density is a measure of how much mass is contained in a given volume. All matter has density, but different materials can have different densities depending on their composition and the arrangement of their atoms or molecules. Some common materials with high density include metals like lead or gold, while materials like air or foam have low density.
The density of high molecular weight high density polyethylene (HMHDPE) typically ranges from 0.945 to 0.965 grams per cubic centimeter.
This is a solid.
Quite low density: 0.968 g·cm−3
Density
This is a liquid.
Yes, the population density is quite high.
High density is a characteristic of a Gas. When something has a high density it means there is a lot of a certain gas, in one area.
high density have more matter per unit of volume (a box with a lot of circles) low has fewer matter per unit volume (a box with less circles)
In general, the solid state has the highest density due to the closely packed arrangement of particles. Liquids have a lower density compared to solids because particles are more spread out. Gases have the lowest density as their particles are far apart and can move freely.
You can use a centrifuge machine which spins small test tubes at very high speeds causing the lower density matter to rise and the higher density matter to sink. This leaves you with a density gradient of the different types of matter in your mixture.
It's not necessary. If a compound has high optical density, it means that it absorbs more light at the given wavelength than some reference compound. There is no simple relation between density of matter and optical density. Even more I am pretty sure you can find a lot of compounds with lower densities (of matter) but having high optical density.
The density of an object describes how tightly packed its matter is. It is calculated as an object's mass divided by its volume. A high density indicates closely packed matter, while a low density indicates less tightly packed matter.
void is anti matter in high density mass which due to high gravitational force may cross the threshold of the speed 3 x 108 km/sec to form matter.