Chemical Reaction
A chemical reaction is an action that leads to the transformation of one set of chemical substances to another. A well known chemical reaction is when mixing ethanoic acid with sodium hydrogen carbonate. Chemically the ethanoic acid reacts with the sodium hydrogen carbonate to form carbon dioxide gas and water. The carbon dioxide gas produced rushes away from the water. This is seen as bubbles.This is a double replacement reaction and the sodium ion reacts with the acetate ion. Giving Sodium Acetate And a H+ Ion reacts with the bicarbonate ion giving carbonic acid which decomposes into water and carbon dioxide. This reaction happened because of a substance called entropy. Entropy is a property of matter that can quantized by randomness of disorder. An example will be how a solid has a lower entropy than liquids and gasses due to the fact that molecules of gases have an increase freedom of movement. Entropy is one part of why chemical reactions happen, lets look at the other parts. Chemical reactions occur when two compounds collide in a certain way and with a certain amount of force. The reason they are needed, is because they are used to make and break bonds. Bonds are of two kinds – ionic bonds where a positively charged species is attracted to a negatively charged species (a bit like magnets) and covalent bonds where two atoms are attached more as if they were tied together. A quick reminder: Covalent Bonds are chemical bond that are used to share electron pairs between atoms.
In both cases energy is needed to break these initial bonds to start a reaction – even if more energy is returned when any new bonds are formed to give new substances. This is called the “reaction activation energy barrier” and explains why we don’t all just burst into flames (among other things). As I said before for a reaction to take place, the molecules have to collide. This that rust are also chemical reactions. For example, a steel garbage can. Iron and oxygen combine in the atmosphere which creates the rusting. The garbage can rusting is known as a physical change. And it is a change that is visible when it happens. A burning candle is an example of a chemical change because it is through the combination of wax and oxygen in a reaction that produces heat, light, and carbon dioxide. Reactions don't always happen, and this is because the molecules where not able to match correctly.
5 Types of Chemical Reactions
- Combination or Synthesis Reaction. A combination or synthesis reaction is one, where a new product is synthesized by combination of two or three reactants.
- Decomposition Reaction.
- Displacement or Replacement Reaction.
- Acid Base Reactions.
- Combustion Reaction.
Fun Fact:
- Chemical Reactions are used to create the energy we use.
Sources:
Bright Hub Education. (2018). What Causes a Chemical Reaction? The Difference Between Simple & Violent Chemical Reactions. [online] Available at: https://www.brighthubeducation.com/science-homework-help/105155-what-causes-chemical-reactions-with-examples/ [Accessed 14 Oct. 2018].
Education.vic.gov.au. (2018). Chemical reactions. [online] Available at: https://www.education.vic.gov.au/school/teachers/teachingresources/discipline/science/continuum/Pages/chemreactions.aspx [Accessed 14 Oct. 2018].
Trello.com. (2018). Trello. [online] Available at: https://trello.com/b/6p3EQ3EO/chemical-reaction-project-rahenya-layne [Accessed 14 Oct. 2018].
https://www.google.cm/imgres?imgurl=https://upload.wikimedia.org/wikipedia/commons/thumb/1/17/Covalent.svg/200px-Covalent.svg.png&imgrefurl=https://en.wikipedia.org/wiki/Covalent_bond&h=241&w=200&tbnid=Qk21ARFQSG-vcM:&q=covalent+bond&tbnh=160&tbnw=132&usg=AI4_-kRojE12gYVUfOEVdj93vNGqV4rWpg&vet=1&docid=K_7tIH0B_uJEPM&sa=X&ved=2ahUKEwjY_o2aiYjeAhVIyqQKHYFcBp8Q9QEwAHoECAYQBg
https://www.google.cm/imgres?imgurl=https://study.com/cimages/multimages/16/double_displacement_reaction.png&imgrefurl=https://study.com/academy/lesson/double-displacement-reaction-definition-examples.html&h=290&w=600&tbnid=opLewgsykiHkQM:&q=double+replacement&tbnh=103&tbnw=214&usg=AI4_-kS23ePepctekhL7dxIhs7OaNuo_Zg&vet=1&docid=yJCe5mlS1XrrXM&sa=X&ved=2ahUKEwiUmKGNiojeAhWCCewKHdtLAOAQ9QEwAHoECAQQBg
Video:
https://www.youtube.com/watch?v=8m6RtOpqvtU
Comments
Post a Comment