ok, i have a huge chem test soon and i need help.
its kind of like a midterm and its on ALOT of topics. i am really bad with chem, so I need help. also, my teacher doesnt teach and i need help with these topics...can someone help me please?
have missed my chemistry class for acouple weeks b/c i have been sick. my teacher just gave me a ton of work which i need help with. can you teach me about these topics please??
thankss
What is the purpose of the actvity series?
What is the mole(value, what it is used for)?
Discuss the Gas Laws- (Boyle, Charles, Ideal)
Discuss endothermic/exothermic reactions.
What are reactions at equilibruim?
pH scale --acid base and neutral(examples)
2007-02-02 07:56:50 · 3 answers · asked by nice too meet you. 4 in Science & Mathematics ➔ Chemistry
hey i dont really need long answers
as my teacher always say KISS (keep it short sweetie)
2007-02-02 08:02:55 · update #1
Ok. Good luck.
mole- the standard unit of nubering in chemistry. is equal to 6.023*10^23 representative particles, i.e. atoms for elements, molecules for compunds, etc. The atomic weight of an element is equal to the wiehgt of a mole of that element in grams.
Exothermic reaction- a chemical reaction where energy is relseaed. if you were to feel the test tube, it would be hot. because energy was lost, the energy of the products is less than the energy of the reactants. The products are therefore more chemically stable.
Endothermic reaction- a chemical reaction where energy is absorbed. The test tube would feel cold. The energy of the products is greater than the energy of the reactants. the reactants are therefore more stable.
pH- shows the acidity or baseness of a substance. scale goes from 0-14
Base: bleach; high pH, produces H^3O+ ions in water
acid: hydrochloric acid: low pH, H+ ions in water
neutral: has a pH of 7, such as pure water.
2007-02-02 08:49:56 · answer #1 · answered by Anonymous · 0⤊ 0⤋
First off, I am almost positive that your teacher, teaches very well. The teacher only presents the material, you have to put in the time to learn it. Its not his/her fault if you don't do that.
a. Activity: In calculations involving concentrations, the activity of a compound is often used instead of the concentration, because... for example if you dissolve 1mole of Nain water it might behave as if only 0.9 mole of NaCl was dissolved. In the calculation the concentration used would be 1.0, but if you use activity you use 0.9. The 0.9 value represent what is really occurring.
b mole, is just a number. Like a dozen is 12, a mole is 6.022x10^23. It is used to convert between molecular weight, mass and moles... there is really to much to write. Go read your text book.
2007-02-02 09:18:57 · answer #2 · answered by Bea S 2 · 0⤊ 0⤋
effective, have self theory in your self, and in case you have been attending all your training then it fairly is available to revise for each and each and each and each and all the three assessments! you regardless of if have 48hrs approx. So earnings on it!!
2016-11-02 03:52:41 · answer #3 · answered by Anonymous · 0⤊ 0⤋