Matter.

Matter.

1. Matter is everything that has mass and occupies space (volume)

   • To describe something, we need to know its properties. These can be:
     • General: They are used to differentiate matter from non-matter, but can't be used to identify materials. Some examples are length, surface area, volume, mass and temperature.
     • Specific: They are used to differentiate some types of materials from each other. Some of these include density, PH, thermal conductivity, electrical conductivity, herdness, luminous intensity, etc.
   • Mass is the amount of matter in an object. Its SI unit is kg. Volume is the amount of space an object occupies. This is calculated in cuboids by multiplying the three main lengths: Length, Width and Height. Its SI unit is m^3, but L can also be used. 1dm^3 = 1L
   • The three most important calculations in matter:
     • Density = Mass * Volume
     • Volume = Mass/Density
     • Mass = Volume * Density

2. Matter can be a mixture or a pure substance.

   • A mixture can be decomposed by using physical methods (Sedimentation, magnetism, decanting, filtering and centrifuging for heterogeneous mixtures and distillation and crystallisation for homogeneous mixtures.)
     • A mixture can be homogeneous, if only one component is visible ( mixture called a solution). This means the solute's particles are smaller than 1 nm.
       • A solution has the following elements:
         • Solute: the element dissolved in the solvent, usually is in a smaller quantity than the solvent. There can be more than one solute in a solution.
         • Solvent: the element in which the solute is dissolved. If a solution contains water, this will always be the solvent.
       • The concentration of a solution is how much solute there is in a solution. This is calculated by dividing the mass of the solute by the total volume of the solution.
       • A solution can be diluted, concentrated or saturated, depending on how much solute it has.
         • The solubility is the concentration of a saturated solution. It depends on temperature, the solute and the solvent.
         • The excess solute in a saturated solution is called the precipitate.
     • Or heterogeneous, if more than one component is visible (which can be a colloid if the particles are larger than 1 nm but smaller than 100 nm or a suspension if the particles are larger than 100nm. In this case, the solid suspended in the suspension settles down after a while.).
       • In a suspension or a colloid, the Tyndall effect happens. This is the effect of light dispersion thanks to the size of the particles.
   • A pure substance is a type of matter which can only be decomposed by using chemical methods.
     • Elements: A type of substance consisting of an only type of atom (Gold, Hydrogen, Helium)
     • Compound: a type of substance which consists of several types of atoms.
   • How to tell apart a compound from a heterogeneous mixture:
     • A compound's substances are proportional, for example, in water, for every atom of oxygen, you have 2 of hydrogen.
     • A heterogeneous mixture's composition (for example, a latte) doesn't have to be proportional. That way, if you add a high amount of coffee and a lower amount of milk, it will still be a latte. The same goes for other materials, such as granite, cheese, or even pencils.