The Idiots Guide to Everything: Basic Chemistry

Posted on March 11, 2013

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Because everything.

BASIC CHEMISTRY

I didn’t really pay much attention during science classes in school. I can’t remember the exact reason for this, but I can only assume it was a multitude of things. Being a teenager, there was just too much going on around me to have any time to dedicate my brain to science class. Some sport was happening, or some girl got prettier, or we started something cool in geography class, there was always something more interesting going on than science. Little did I know how important science is to the world that we live in. In fact, it is the world we live in. Chemistry was one third of the science spectrum in school, and from memory it was elements and chemicals and sitting near the back not paying much attention. I didn’t realise that chemistry is everything. Well, chemistry is in fact the study of matter, and that changes that take place within it. Sounds simple enough right? Well, yeah, it is, until you realise that EVERYTHING in the ENTIRE UNIVERSE is made up of matter. It is the name given to everything we touch, see, feel, smell and everything in between that our senses can’t even begin to fathom. Anything that is made up of atoms (read: everything) and molecules, has any sort of mass and takes up any sort of space. The study of chemistry is the study of everything at its most basic/complicated. Therein lies its beauty.

I do remember there being various physical states of matter, but in my head there were 3, these being Solids, Liquids and Gases. It turns out that there are actually 5, the other 2 being Plasmas and Bose-Einstein Condensates. Each of these are defined by the physical states of their molecules and atoms. Elements and compounds can move from one state to a different one without any chance in their atomic parts. Indeed, salt is the same molecular structure whether it is gas, liquid, solid or whatever. The physical state of matter changes with a different density, different pressures, temperatures and changes in other physical properties. For instance, when the temperature of something is increased, the matter becomes more excited and energetic, leading to a change in state. If you give a liquid enough energy, it will become a gas. On the spectrum, a solid is the least energetic state, then going through liquid, gas and plasma in ascending order. So a compound or element can move from phases to phase, but it will always be the same substance. Let’s look at the different states.

 

SOLIDS

Solids are most often than not hard, because the molecules inside are packed tightly together, but they can also be soft. They can be big or small, and everything in between. Solids will always hold their shape, they don’t flow to fit their surroundings. The atoms inside a solid don’t move too much, and are stuck in a specific structure. Solids can be made up of many things, be it a pure element or a variety of compounds.

LIQUIDS

What are liquids? Its a lot harder to explain when you try not to use the word ‘liquid’ Well, water is a liquid. Blood is a liquid. Beer is definitely a liquid. It is the state that is found between solid and gas. The atoms in a liquid are more spread out than those in a solid, but less spread out than a gas. Liquids will always fill the shape of their container, from the bottom upwards. They are pretty difficult to compress, and it is the intermolecular forces that keep the molecules of liquids together. When you dissolve any material in a liquid, it is known as a ‘solution’. More on them in a moment.

 GASES

Gas is everywhere. Literally. Our atmosphere is essentially a big layer of gas surrounding the earth. The atoms in a gas are hugely spread out, and are bouncing round on a constant basis, energetic little things that they are. A gas can fill a container of any size or shape, as the molecules will always spread out to fill the whole space. They can also be compressed with little pressure, but gas will always be desperate to get out. Take for instance opening a can of Lilt, when you pop the cap there is a quick escape of gas, and gas will leave the liquid steadily until there is no fizz left, and flat Lilt is HORRIBLE. Whenever you hear the word ‘vapour’ by the way, this means the same as gas. A vapour is a gas that is usually found as a liquid, but happens to be a gas.

So whilst talking about liquids, the term ‘solution’ was mentioned. What is a solution? Solutions are groups of molecules mixed up in a completely even distribution. In a solution, everything is spread out and mixed together. This is not to be confused with a ‘mixture’, which is similar but has more of one thing on one side. A good way to differentiate this is with the effect of sand and sugar in water. When sugar is dissolved in water, its spreads throughout, and is a solution. Sand however, will not dissolve in water, it will just sink to the bottom, and is a mixture. Pretty much anything you can think of can be a solution. The simplest solution sees 2 substances combined. The substance that will dissolve into the liquid is known as the ‘solute’, and the liquid that does the dissolving is called the ‘solvent’. The amount of solute that will dissolve is defined as ‘solubility’. Particularly foggy looking solutions are known as ‘colloids’.

On infrequent occasions, 2 or more metals can be mixed together. These are known as ‘alloys’. These can also include small amounts of non-metallic elements. Alloys exist mostly to improve specific qualities of the original metal. However, when a metal is combined with mercury, this is known as an ‘amalgam’. Mercury is unique in that it is the only metal that is a liquid at room temperature. It is also very volatile, and you would do well to stay away from it. The final stop on our list of mixtures are things called ’emulsions’, which are special colloids that are a mix of oils and waters. They are 2 very separate layers before mixing, and over time they will separate back.

So there you have it. A very basic guide to the first steps of chemistry.

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