Chemistry Definitions: Accurate & Concise for Tests

[MadmanMurray]

I've been learning chemistry for a good while and now I'm doing it in college and what I've noticed is I don't do well in tests because I have trouble explaining what I know. Even though I understand the concept my answers aren't always adequate and I lose marks. Can anyone recommend a site that gives the most accurate and concise definitions of chemistry terms? I'm not going to memorize definitions but I'd like to see how these things are defined by the pros.

I already know most of what's going to be on the test. For example one of them will be "Explain what a covalent bond is". I know well what a covalent bond is but here's how I'd answer it. "A covalent bond is a chemical bond in which two atoms with small differences in electronegativity share their valence electrons so that each atom has 8 electrons in their outer shells."

Is that a reasonable answer? The problem I find is that the teacher might assume I have a lack of understanding because I don't mention everything for example I left out "the reason each atom ends up with 8 electrons is because their combined valence electrons amount to 8 so technically they have complete octets". I write slowly so I can't give big 5 line answers for every question.

Another problem is my terminology. The teacher never thought the class the word "valence electrons" he just refers to them as "electrons in the outer energy level of the atom" and he never says octet so he might take marks off me for not explaining it his way.

Any suggestions on how I should deal with this test? The teacher doesn't give out notes so I can't memorize his definitions. I don't like memorizing definitions though I learn the concepts and then define as best I can. Its more of an English test than a chemistry test in my case because the hard parts properly explaining what I know.

 

[kingdomof]

To begin with, a covalent bond does not require that each atom forms an octet; it just brings the two atoms to a higher stability through the sharing of an electron. Also, small is a relativistic term, which does not make good scientific definitions. You might want to put down exact numbers, if you wish to characterize how electronegativity differences play a role the polarity of the molecule; however, I highly doubt that the teacher was looking for this explanation and wanted a much more elementary definition. A definition for covalent bond that I would use in your circumstances would be "a bond between two atoms in which an electron is shared to achieve a more stable situation for the two atoms through the creation of a molecule." An example of why you cannot simply define a covalent bond as an octect forming situation is that of boron compounds and the various spd hybridized compounds, in case you are confused as to why it does not necessarily form an octet. Also, more than one covalent bond is able to be formed on a single substituent atom of a molecule.

With that said, science does require proper mastery of English and mastery of a precise theoretical standpoint of how you are able to describe things. The definition you gave, and I'm very sorry to possibly offend you, is wrong. I too was like you when I first took a real science class and did not use precise wording for concepts, but once you learn some more, you will realize precision equates mastery.

Overall, you were wrong, and your teacher is right. Spend more time on reading the textbook and thinking about why each word is there in a definition.

Good luck.

 

[quicknote]

As a fellow scientist, I can definitely relate to your struggles with tests and explaining concepts in chemistry. It is important to remember that in order to do well on tests, it is not just about understanding the concepts, but also being able to effectively communicate them in a concise and accurate manner.

One suggestion I have is to practice writing out definitions and explanations in your own words, using simple and clear language. This will not only help you understand the concepts better, but also improve your ability to explain them effectively. Additionally, I would recommend seeking out resources that provide accurate and concise definitions of chemistry terms, such as reputable textbooks or online resources from reputable institutions.

It is also important to communicate with your teacher and let them know about your struggles with terminology. Perhaps you can ask for clarification on certain terms and their definitions, or even suggest using the terminology that you are more comfortable with in your answers.

Lastly, I would advise against trying to memorize definitions, as this may not always translate to a deeper understanding of the concepts. Instead, focus on understanding the underlying principles and being able to apply them in your explanations. With practice and patience, I am confident that you will see improvement in your test performance and ability to explain chemistry concepts accurately and concisely.