So I'm taking 6 classes this semester, 5 are eight week courses and are split up, and I have a Biology 1 course that is 16 weeks, but having a hard time understanding a lot of this since I never took either biology or chemistry in high school.
I've found a couple of sites online for helping explain this, but does anyone have a great one for explaining to someone who hasn't taken the highschool versions of biology?
I have a quiz tuesday and am having a hell of a hard time understanding some of this. Anyone I saw how many people had math help sites linked and am hoping someone out there has a biology one.
What topics are you studying right now? I have some powerpoints on cellular structure & function, proteins, carbohydrates, lipids, and cellular respiration. It is from my class but it has pretty good info. What text book are you using? The text book could have a website.
Actually I'm on those subjects right now. First 3 chapters is what the quiz is on Tuesday. Chapter one is basically cells, characteristics of living, metabolism, adaptation and a few other things like that.
Chapter two is the periodic table, Bohr models and electron configurations, different types of bonds and the pH scale. Chapter 3 is organic compounds, dna/rna, carbohydrates, lipids, the different saccharides, briefly touches base on steroids, and a lot on protiens.
I thought I had a decent understanding of most of that from reading a ton on diet and how food effects your body but I'm a little behind the curve in this course. The book is "Biology, volume 1" Was specifically written for my community college (I hate these books), however, it was written by Eldra Soloman/ Linda Berg/ and Diana W. Martin, who have apparantly written a few other books.
I checked the website, and it has a registration thing but its only good if the teachers have opened things up, which my teacher surely has not.
It wouldn't be such a hard class for me if I could understand half of what this teacher is saying, but he's Indian or middle eastern and I have a hard time with his lectures. Also I can't drop the course because UF looks at it very badly for and courses needed for transfer.
Excuse my bad grammar, I've literally gotten an hour and a half of sleep since friday night, I've been writing papers for other courses and now im just moving onto studying this.
edit: The worst part is he hardly tells us whats on the quiz. The first quiz I don't think a single person in the class got more than 7 our of 10 questions right.
All I can say is study your ass off for the quiz, go over all the major points in the chapters that the quiz is covering (usually there are good summaries and questions, too). Make sure you really understand the terminology, too; look up a word if you don't know what it actually is (i.e. vesicle).
I can send you my powerpoints via email if you want. They can only help so much though because the quizzes/tests are going to be specific to what you actually went over.
Your going to COmmunity College? What are you majoring in? If its not Biology then fuck drop it and take some easy course thatll transfer like Geology or Geography. If your majoring in Buisness or Social Science there is no need for you to take Biology IMO unless you wanted to learn about it.
Okay I have a question. I'm having a hard time understanding electron orbitals. I understand how there is a maximum of 2 electrons per orbitals, and there can be multiple orbitals with the same principle energy level. What I don't understand is how the electrons move, I've always thought it was in a spherical motion around the nucleus, yet the book is illustrating that 3 or the 4 orbitals on the same energy level move in seperate nontouching "dumbbell shapred orbitals"
From the looks of this if they continued on that path in an circular motion they would go through the nucleus. This makes no sense, perhaps its because I'm trying to understand something in 3 dimensions looking at a 2d picture.
Bohr models make plenty of sense though....
edit: Okay, another question regarding avagadro's number and mol's. I understand that 1mol of any substance is the same as the atomic mass of it, so H20 is 18AMUs so it is 18 grams. And that glucose is 180AMUs and 180grams, but how the hell the hell does that mean they have the same amount of atom's in it? It makes no sense to me.
ok, the first orbital can only hold 2 electrons but the next can 8 electrons max, if it has more than 8 it forms a third orbital which holds the extra..If it has one for example in its third orbital it may give it up to another atom and become an ion. Atoms like to be even.. equal electrons and protons. The electrons move erratically in orbit.. we only know something like 80% of the time where they are in orbit.. they move like crazy.
Well they dont exactly have the same number of atoms.
1 mol of any substance has 6.022x10^23 atoms or molecules. 18 grams of H2O is one mol (close enough) so it has 6.022x10^23 molecules (since it is a molecular substance) times this by 3 to get number of atoms. 180 grams of glucose is one mol, so it to has 6.022x10^23 molcules (so it has 6.022x10^23 C6H12O6's) times this number by 24 to get number of atoms. if it was an element (eg sodium) and you had one mole it would be 6.022x10^23 atoms.
Now how can glucose have the same number of molecules as water when glucose has a much larger molar mass. Well it's because of just that, Glucose has a much larger molar mass. A molecule of Glucose is heavier than a molecule of water so a mol of glucose (which will have 6.022x10^23 molecules, just the same as 1 mol water) will have a greater mass than that of water.
Petermus has sortof explained the electrostability of an atom with complete orbits and pairing of atoms etc.
The actual nature of the atom and other particles is complex. Bohr and Einstein are remembered by simplifying this complex nature with simple models. The Bohr model is a hydrogen atom with 1 electron orbiting around it. In the field of quantum dynamics, an electron has a parameter of spin which can be + or - 1/2. This is electron spin (there are other spin parameters in quantum dynamics). An electron will always try and find an electron with opposite spin, hence the pairing of electrons.
An electron orbiting a nucleus exhibits this strange behaviour where it can be a particle or wave, such as light. Therefore you should consider the electron orbiting around a nucleus in a circular motion as a wave. It is considered a standing wave since standing waves have no net energy transfer. If it was a normal wave and had energy transfer, it would lose energy as the electron orbited, meaning an atom would be using energy to stay in existence which would lead to it eventual collapse and a collapse in the universe.
[Due to the consideration of the electrons as waves you bring in the Heisenberg uncertainty principle which means with a given particle you can only know either its energy or position at any given time, not both at the same time. This brings in the use of probability and electron clouds etc.]
Going back to your book and diagrams showing orbits going through the nucleus, remembering the standing wave theory, energy levels except 's' have a node exactly at the nucleus resulting in no interaction. S energy orbitals have an anti-node at the nucleus mean it competely avoids it.
Each electron has a set of quantum mechanical parameters. No two or more electrons can have the same parameters. This is the Pauli Exclusion Principle.
Electrons don't move in a fixed pattern around the nucleus. It's more like a cloud of electrons moving around randomly. Why are you learning this in Biology? Seems like a Gen. Chem. topic to me. Anyway, in my opinion it sounds like you're having trouble with the fundamentals. The Internet is great for finding facts and clearing up minor confusion, but you are wasting your time trying to figure stuff out on your own when you are having trouble grasping concepts. Going to someone knowledgeable will be MUCH quicker. Ask your teacher for help, go find a tutor (I'm sure your CC has some kind of help available), do whatever you have to. The Internet is not time efficient for something like this. Trust me.
You don't really have to understand how electrons move because at your level of chemistry they're not telling you the truth anyway : ) The truth is that an electrons relation to the nucleus is unpredictable and random, you can only determine the PROBABILITY of where it is. It's confusing but just practice looking at your periodic table and identifying orbital levels. 1S2, 2S2, 2P6, 3S2, etc. Pay attention to the d orbital which is on a different energy level.
Regarding the other question, all you need to know about mol's is that it's just a number. 6.023 X 10^23. You can have a mol of babies, or hippos and it's still the same number. What you need to understand is that different atoms have different masses, so when you assemble 1 mol of that atom or compound or molecule the mass is called the molar mass. You will need a lot of practice with that concept.
So quickly: one mol of H20 molecules weighs 18 grams and on mol of Na weighs 23 grams. If you know that Water reacts with Sodium (Na) like so, 2H2O + 2Na --> 2NaOH + H2, how many grams of Na will you need to completely react with 36 grams of water? How many grams of NaOH are formed? Think moles and look at the molar ratio of the equation.
Very true. Chemistry especially is all about the concepts with some things you just have to memorize like orbitals. I'll give you some pointers if you want, but you really do need someone to explain the concepts first hand.
Thanks a ton for the replies everyone. My brain is completely fried from not sleeping much the past couple nights writing religion papers, doing this, and preparing a speech to deliver tomorrow. I would have went to a tutor at the school but they don't work the hours I have available on the weekends. Well, atleast this weekend.
In a few moments when I wake back up I'll probably post again. I'm understanding most of whats going on after reading over it a couple times, but my book doesn't teach in the way I learn with specific contrasting examples so I'm dying.