While the introduction of general chemistry, which covers all the chemistry basics, usually takes place at high school, this is a subject that can go way beyond university education. In fact, it is so complex that there is no end to the problem solving of chemistry. It’s also safe to say that regardless of whether you are looking at chemical reaction examples or the difference between physical and chemical change, chemistry is not for everyone.
Studying chemistry is a bit like an acquired taste. Not everyone appreciates the scientific discipline that requires looking at chemical reaction examples or pondering what is a reaction. But if examining elements, compounds, atoms, molecules and ions is for you, or if you desire to know the difference between physical and chemical change then signing up for a Chemistry Basics class is for you.
“The meeting of two personalities is like the contact of two chemical substances; if there is any reaction, both are transformed.” - Carl Jung
General Chemistry offers the student many advantages. Not only is it known as a central science because it combines physics, mathematics, medicine and biology, but it is an expansive field that covers many different practices and interesting topics.
In this article, you will find an introduction to some of the questions around chemistry basics, chemical reaction examples, the elements, periodic table and liquids and gases to name just a few.
Whether science is of interest to you or not, this article could give any individual an idea about the general chemistry basics. Next time you find yourself in a discussion about the difference between physical and chemical change, you never know, you might be able to understand and ask the right questions.
What Is a Reaction?
Did you know that chemical reactions are happening all around us all the time? You might be wondering but what is a reaction? When we cook, make a fire and even breathe – we are creating a chemical reaction.
When a chemical reaction takes place, the ions or molecules are actually rearranged and changed into a new structure. It’s important to remember that the atomic nucleus is untouched and only the electrons transfer to create chemical bonds. The atoms from the elements do not change and stay the same from start to finish during a chemical reaction. This amazing discovery was the work of Antoine Lavoisier, one of the world’s most famous chemists.
The Difference Between Physical and Chemical Change
It is worth noting that chemical reactions differ from physical changes. The most notable difference between physical and chemical change is that when a chemical reaction occurs, atoms form new products, compounds and molecules. However, when a physical change occurs, atoms retain their original arrangement.
It is quite marvellous to witness the molecular change that goes with a chemical reaction. Some of the chemical reaction examples to look out for to confirm a chemical reaction can include temperature change, bubbling or colour change.
The molecules and atoms that interact are called reactants, while molecules and atoms that are produced as a result of the reaction are called products.
An example of a chemical equation could read as follows:
Reactant 1 + Reactant2 → Product 1
With some general chemistry basics, you could write this in shorthand:
aA +bB → cC
Chemical reactions are divided into four types:
- Direct combination or synthesis
- Single replacement
- Double displacement or metathesis
As mentioned there are many chemical reaction examples taking place around us at all times. Here are a few more noteworthy examples:
- Creating a flame or lighting a fire
- Cooking whether that’s frying or boiling food
- Observing the progression of a rotting banana
- Grilling a hamburger patty
All of these are really just the tip of the iceberg and possibly examples of what will either be discussed or observed in your general chemistry basics class, however, if you want to get ahead of a syllabus that can be very complex, there are a few things you could do:
- Follow general chemistry channels on YouTube
- Do your own Google research to gain additional understanding on the topics in your syllabus
- Find a private chemistry tutor using a platform like Superprof
Getting back to the difference between physical and chemical change, remember that a chemical element is already in its simplest form, it is pure and not able to be broken down any further.
To date, scientists over hundreds of years have discovered 118 chemical elements. So far, 94 of these actually commonly occur throughout nature, while the other 24 are man-made or synthetic.
A few fun facts that you will probably hear in a general chemistry basics class is that the most plentiful element in the universe is hydrogen, while the on Earth, it is iron. But for both the human body and the earth, the most common element is oxygen.
Elements have a single atom and are characterised by the number of protons found in the nuclei their atoms. This is also known as its atomic number which is indicated by the number Z.
When elements are not mixed, they remain in their purest state and will have the same number of protons. When an element is mixed it will have different protons and atoms.
There are only a few elements that are pure and have not been combined. Some of these include silver, copper, gold and sulphur. On the other hand, an example of a mixed element would be the air of the atmosphere around us which has been mixed with oxygen, nitrogen and argon.
Different elements are found on the periodic table, the first of which is hydrogen, which only has one proton. The second is helium with two protons. Lithium is third with three protons. The protons and elements keep going all the way to 118 on the periodic table – which by the way is the most recently discovered element called oganesson.
The Periodic Table
The most commonly used arrangement of elements is the periodic table. Each element is organised by an atomic number or electron configuration and its recurring chemical properties. Rows are called periods, while columns are referred to as groups.
When it comes to the columns, there are 18 on the periodic table. Elements that are similar in terms of their chemical behaviour are grouped in the same place. Seven of the groups, so far, have the following names:
- Group 1 is called Alkali metals
- Group 2 is called Alkaline earth metals
- Group 15 is called Pnictogens
- Group 16 is called Chalcogens
- Group 17 is called Halogens
- Group 18 is called Noble gases
If you are wondering what the background colour on the chart means it is used to identify subcategories! These are non-metal, metalloid and metal. It’s good to keep in mind at this point that even though categories do not differ, there are varying types of periodic tables and colours are not always standardised.
There is no doubt that trying to understand and even memorise the periodic table will be foundational, not only to your chemistry basics but your whole chemistry career. When it comes to the finer points, this is an area where a tutor would be really helpful.
Lewis Structures and Chemical Bonding
What is chemical bonding?
This is the attraction between ions, atoms and molecules to form chemical compounds. Each bond will have a unique strength as a result that some are stronger, for instance, metallic bonds, ionic and covalent, while others are weaker. Weak chemical bonds include the London dispersion force, hydrogen bonding and dipole-dipole interactions.
Stronger bonds that hold molecules together are permanent while weaker bonds, which break apart after a while are considered temporary. What’s interesting is that it does not matter how long the bond lasts, all are necessary to run the chemistry of our own bodies and indeed, life itself!
Interestingly, scientists have found that the most common cause for the forming of chemical bonds is because atoms are seeking to achieve the most stable form of energy that they can.
Another interesting fact is that in both life and in chemistry, opposites attract. The positively charged protons with a nucleus cause a pull of the negatively charged electrons that are circling it. This creates a chemical bond!
Here are a few types of chemical bonds:
- Ionic Bonds: table salt is a good example of ions forming between opposite charges. The negatively charged ions and the positively charged sodium ions are attracted to each other, thus forming sodium chloride.
- Covalent Bonds: this is when atoms become more stable in nature by the sharing of electrons as opposed to gaining or losing them. Covalent bonds are more common in molecules of living organisms than ionic bonds. More electrons shared between both atoms will result in a stronger covalent bond.
- Polar Covalent Bonds: here, electrons spend more time close together and are unequally shared by the atoms. There is an unequal distribution of electrons between the atoms and charges develop in differing parts of the molecule.
- Nonpolar Covalent Bonds: this happens when two atoms of the same element form. It can also happen when atoms of differing elements share electrons equally.
- Hydrogen Bonds: when a polar covalent bond has hydrogen it contains a slight positive charge because the electrons pull towards the other element. This pull causes the hydrogen to attract negative charges.
Lewis Dot Structures
Lewis dot structures are something that you will certainly come across in General Chemistry. This is when bonds are shown between atoms and molecules while lone electron pairs potentially still exist in a molecule.
First introduced by Gilbert N. Lewis in 1916 in his article titled The Atom and the Molecule, the concept expands on electron dot diagram through the adding of lines that show the shared pairs of a chemical bond.
The Lewis dot structure is a quick method that reveals the valence electron configuration concerning separate atoms in the case of no previous bonds or connections.
Acidity and Basicity
Something else that will certainly come up in chemistry basics is distinguishing whether a substance is an acid or a base. A chemical reaction between a base and an acid is called an acid-base reaction and can be used to establish the pH of a liquid or substance.
Here are some of the commonly used acid-base theories that you are likely to come across when asking the question of what is a reaction!
- The Svante Arrhenius theory on acids and bases
- The Gilbert Newton Lewis theory on acids and bases
- The Bronsted-Lowry theory on acids and bases
Amongst other things, acids can be distinguished by their corrosive behaviour, while bases feel slippery and won’t change the colour of litmus paper.
Here are some of the different types of acids you might use when looking for chemical reaction examples:
- Lactic acid
- Citric acid
- Carbonic acid
- Ascorbic acid
And here are few of the common bases you might come across when looking for chemical reaction examples:
- Household ammonia
If acids and bases are potentially an area of interest for you, the best way to improve your knowledge would be to gain knowledge regarding the theories mentioned above.
Chemistry is a diverse and complex subject where students often feel left behind in group or classroom settings. Like mathematics, if one principle is not grasped it can potentially kibosh a student’s experience of an entire syllabus. It is one of those important subjects where a little extra tuition can add enormous value. Find out about Superprof tutors in your area and have these concepts explained in the comfort of your own home and at your own pace.
Alternatively, you could even find a Superprof tutor online, all you need is a webcam and an internet connection. Your private tutor could take you through general chemistry basics, show you chemical reaction examples and even explain the difference between physical and chemical change. It all depends on you!