Chemistry help?I just don't understand?
*** 5 *** an unsaturated solution can dissolve more solute. a saturated cannot. usually the solubility is temperature dependant. so...you can... change the temperature (usually lowering the temp makes the solute less soluble but NOT always) or you could add more solute. or you could evaporate some solvent. *** 6 *** add more solute. if it dissolves, the solution was not saturated. *** 7 *** molarity.. moles solute / L solution molality... moles solute / kg solvent mole fraction.. moles of one species / moles total mass fraction... mass of one species / total mass volume fraction... volume of one species / total volume v/v %... volume of solute / volume solution x 100% w / w %... weight of solute / weight of solution x 100% w / v %... weight of solute / volume of solution x 100%
I completely do NOT understand this chemistry question, if anyone can help me out, I'd appreciate it! Thanks!!?
[DOC] Chapter 8 Chemical Reactions File Format: Microsoft Word - View as HTML Use the activity series with single replacement series to determine if a ... is a good indicator of possible reaction type and thus possible products. ... cabot.k12.ar.us/schools/chs/tharp/PreA... - Similar pages # [DOC] Chap. 4: Chemical Reactions File Format: Microsoft Word - View as HTML .from the following and balance Practice: predict products ... of the equation. + and OH- .Cancel water molecules if possible on same sides into water. ... facweb.eths.k12.il.us/kohnkenr/AP%20ch... - Similar pages
Chemistry Questions Please explain your answers so that I can understand in future. Thanks.?
The Sears Tower in Chicago has an approximate floor area of 418,000 m². How may square feet of floor is this? A six-pack of 12 oz soft drinks sells for $2.59, and a 2.0L bottle of the same soft drink sells for $1.59. What is the cost in dollars per liter for each? Copper has a specific heat of 0.092 cal/(g • ˚C). When 52.7 cal of heat is added to a piece of copper, the temperature increases from 22.4 ˚C to 38.6 ˚C. What is the mass of the piece of copper? Assume that 50.0 cal of heat is applied to a 15g sample of sulfur at 20 ˚C. What is the final temperature of the sample if the specific heat of sulfur is 0.175 cal/(g • ˚C)? When 100 cal of heat is applied to a 125g sample , the temperature increases by 28˚C. Calculate the specific heat of the sample and compare your answer to the values in Table 2.6. What is the identity of the sample?
I have 6 chemistry questions I do not understand. Will someone please help me by explaining these questions?
You don't yet understand atomic mass. A single atom of an element has a very small mass. You can't see an individual atom because it is so small. Chemists have determined the mass of each atom in the periodic table. The mass isn't given in grams or similar units. The mass is given in "atomic mass units" (amu). If we multiply amu's by a very large number (6.022 x 10^23) the mass is numerically equal to amu's, but the units are grams. Carbon atom has an atomic mass of 12.011. If we have 6.022x10^23 carbon atoms, they will weight 12.011 grams. When we have 6.022x10^23 atoms or molecules, we call that 1 mole of atoms or moleculs. 1) the molecular mass of CO2 is the atomic mass of carbon (12.011) plus two times the atomic mass of oxygen (16). The molecular mass of CO2 is 12.011+16+16 = 44.011 atomic mass units. 2) the formula weight (another way to say molecular weight) of NaHCO3 is the sum of the atomic mass of all atoms in the molecule (2 sodiums + 1 hydrogen + 1 carbon + 3 oxygens) or 2*22.991 + 1.008 + 12.011 + 3*16 = 107.0 amu 3) 2.50 moles of H2O. 1 molecule of H2O has a molecular mass of 1.008*s + 16 = 18.016 amu. If we had 1 mole of H2O (6.022x10^23 molecules) the molecular mass would be 18.016 grams. But we have 2.5 moles of water, so its mass is 2.5*18.016 = 45.04 grams 4) Here you must convert 80 dm^3 to cm^3. 1 cm^3 of water at 4 deg C has a mass of 1.00 gram. You can finish this one. 5) The wording here is tricky. Sr(NO3)2 ionizes into 3 units: Sr+2 and two NO3-. So 8.90 x 10^35 ion units would be equal to 2.967 x 10^35 molecules of Sr(NO3)2 (1/3 of 8.90x10^35). Since 1 mole = 6.022 x 10^23 molecules, you have (2.967 x 10^35 / 6.022 x 10^23) moles of Sr(NO3). Once you know the moles, simply multiply by the molecular mass of Sr(NO3)2 to get the grams. 6) No hints here...just do it.
What are ten questions a chemistry major should be able to answer?
What is a chemical bond?What is free-energy?What is the relationship between free-energy, entropy, and equilibrium. (you can describe this in terms of chemical reactions)Why is equilibrium so important to chemists?What is the ideal gas law? Where does it come from?What are isomers? Why are they important chemically?Generally speaking, why does the symmetry of a molecule affect it’s properties?What is spectroscopy? Why is it such a powerful tool for chemists?I took Compound A and mixed it with Compound B, and got an unknown compound C. Give me a list of ways I could determine the chemical structure of C (experimentally and/or theoretically)Helium walks into a bar, The bar tender says "We don't serve noble gasses in here." , what does Helium do?I picked these questions first and foremost because I think I could answer them, but also because I think they touch upon some of the deeper concepts in chemistry and don’t have well defined ‘right’ answers.If I had to pick one, I have to say question 10 would definitely be the most important question. If you couldn’t answer that, well, I don’t know how you would be able to go about calling yourself a chemist ;)
What is the best way to easily understand chemistry?
Here, I can see that many people are advising us to take few help books of chemistry to clear IIT-JEE and neet examination but the question was how we can understand chemistry easily ?? So i will recommend you guys that if you really want to understand chemistry then you have to give atleast 3 hours a day , if you really wanna understand chemistry, there are many theories and there are many books , and when you start learning in strings then you'll understand chemistry , let me give you an example, if you want to understand chemical bonding in covalent bond then you need to start in this mannerLewis structure->Sidgwick-Powell Theory->VSEPR theory -> Hybridization -> Resonance structures ->MOT(MOLECULAR ORBITAL THEORY) When you follow this sequence then you will understand each and every part of it, no one told me to use this method but when I start learning chemistry , I discovered that everything is connected and you just need to correlate them, and there are many books which you can use for references and remember even if you are preparing for iit jee or neet or for any competitive exam then remember that you shouldn't focus on how to memories them, you just have to understand them, chemistry is not like maths in which you can use certain methods to prove something or find a solution of a problem , here you need to give time , I mean you need to spent many hours to understand it and if you understood concepts then you will become master of it, read different books related to it,sorry for my bad English…I have a question for you guys, why boiling point of NH3 is higher than SbH3 and AsH3, give answer with explanation?? The answer of this question is easy.Have a good day
Does all the questions come from ncert exercises in chemistry 12 boards?
Almost all the questions in CBSE Board examinations come from NCERT textbooks. But this does not mean that the questions will come only from NCERT exercises. This is applicable to all the subjects and not just chemistry. The questions are designed so as to test your knowledge of various concepts and hence are not the exact copy of exercise-questions. You will be able to answer them only when you go through and understand all the chapters in the book. Since NCERT books are concise, sometimes certain reference books can also be helpful. You should solve practice papers to get an idea about the type of questions asked in the examination. You can get accurate information about the subject-specific study materials and previous years’ papers instantly at https://www.toppr.com/boards/cbse/. If you are clear with your basics, it would help you in the long run (for entrance exams). I am giving the list of books for chemistry some of which you can refer to for your Board exams:· NCERT Textbook (is a must)· NCERT Solutions by Arihant· Pradeep’s New Course Chemistry· Modern’s ABC for ChemistryAlso understand the fact that only getting marks is not important; always study with the motive that you want to understand the topic and then you would realize that only doing the exercises is not enough.Hope this helps. All the Best!
AP Chemistry questions, need help!?
Please explain how to do this; I want to actually learn and not just get the answer! 1- A hydrocarbon sample with a mass of 6 grams underwent combustion, producing 11 grams of carbon dioxide. If all of the carbon initially present in the compound was converted to carbon dioxide, what was the percent of carbon, by mass, in the hydrocarbon sample? a. 25% b. 33% c.50% d. 66% e. 80% 2- Calculate each of the following quantities: a. Mass in grams of 6.44 x 10-2 molecules of NO2 b. Moles of Cl atoms in 0.0615 g of C2H4Cl2 c. Number of H- atoms in 5.82 g of SrH2 3- How does a balanced chemical equation apply the law of conservation of mass? 4- Assuming that the volumes are additive, what is the concentration of LiCl in a solution prepared by mixing 0.100 L LiCl of 0.0352 M LiCl with 0.500 L of 0.093 M LiCl? Be sure to include all work. 5- Solid magnesium reacts with hydrochloric acid. a. Write an overall balanced equation. b.5.00 g of magnesium reacts with 8.00 g of hydrochloric acid. Identify the limiting reactant. Be sure to include all work. c. How many grams of the magnesium containing product will be produced? Thanks everyone! Please remember to show how you got to the final answer; I don't need answers only, but a walkthrough!
Quite a few Organic Chemistry I questions?
1) SN1 reactions involves a carbocation intermediate and is commonly seen in reactions of secondary or tertiary alkyl halides. In a SN1 reaction, the leaving group usually leaves first which creates a cation on the tertiary carbon. The cation can then attach to the O in H2O. I'm using H2O as my example. SN1 uses protic solvents. Typical polar protic solvents include water, methanol, ethanol, formic acid, hydrogen fluoride and ammonia. 2) The SN2 reaction is a type of nucleophilic substitution, where a nucleophile attacks an electrophilic center and bonds to it, expelling another group called a leaving group (on the opposite end). SN2 reactions are generally favoured in primary alkyl halides (carbon) or secondary alkyl halides (carbon) with an aprotic solvent. This is a key difference between the SN1 and SN2 mechanisms. In the SN1 reaction the nucleophile attacks after the rate-limiting step is over, whereas in SN2 the nucleophile forces off the leaving group in the limiting step. The molecules of such solvents can donate an H+ (proton) is called protic. Conversely, aprotic solvents cannot donate hydrogen bonds. 3) E1 is an unimolecular elimination with a two-step process of elimination ionization (meaning carbon-halogen breaks to give a carbocation intermediate) and deprotonation. You won't see an ionization in E2 reactions. E1 reaction mostly occurs in complete absence of base or presence of only weak base. 4) E2 is a bimolecular elimination with a one-step process of elimination with a single transition state. This typical involves a secondary or tertiary substituted alkyl halides and react often with the present of a strong base. Both E1 and E2 will result in a formation of a double bond or triple bond. Alkane ---> Alkene 5) An addition reation is where TWO or more molecules combine to form a larger one. H2 + O ---> H2O 6) Elimination vs. SN - all elimination reaction will form a double bond. SN1 vs. SN2 - look to see if the reaction is on the primary carbon vs. a Tertiary carbon. Then look for the solvent (Aprotic vs. protic). E1 vs. E2 - look to see if the reaction is on the primary carbon vs. a Tertiary carbon. Then look for the solvent (Aprotic vs. protic).
Need to be explained how to find the answer I have for this Chemistry problem on Bomb Calimotry....?
Hey Clueless! I'm almost sure I've helped you before because I remember your name. At least you know you're clueless. That's where understanding begins. Don't be angry with me, but this is pretty easy. First of all they tell you that the calorimeter has a heat capacity of 850 joules per degree Celsius. That means that when the calorimeter and its parts go up one degree, the whole thing has absorbed 850 joules. Okay, the next thing they say is that you've got 1100 grams of water, and the specific heat of water is 2. 184 joules per gram to raise the temperature one degree Celsius. Well, if it takes 2.184 joules to raise the temperature of one gram of water one degree, how many joules will it take to raise the temperature of 1100 grams of water one degree? Can you see it'll be 1100 times 4.184? So we multiply 1100 x 2.184 and you get 2402 joules. Okay, suppose the Temperature of the whole thing goes up one degree. Well, it takes 850 joules for the contraption and 2402 for the water, or 3252 joules. Can you see? You just have to figure out how much heat energy in joules the whole thing absorbs to raise the temperature one degree. .....And I think you mean bomb "calorimetry". I sure hope I've helped. By the way, I love your name!