Chemistry Definition and 993 Threads

Hi everyone. Just to let you know ahead of time this story might jump back and forth but I'll try my best to keep my thoughts straight. I'm about to graduate with BS degrees in physics and math. I applied to some graduate programs but I don't think I'll get into any because my grades were...

Sorry to disturb. I'm really bad at chemistry and i was hopping i could find some help... My major doubt is about Titration for now and how to find what is asked even if i got the data needed. Homework Statement 25.0 cm3 of 1.00 x 10-1 mol dm3 hypobromous acid ( HBrO ) solution is...

I have an interest into looking into the chemistry that goes into making the foods today. I'd like to know what goes into the tastes and smells. So I was wondering if anyone had any suggestions as a good jumping off point for this topic. Any articles or books would be great. I have access to...

Homework Statement From burning 7,2 litres of an alkyne, we get 26,4 grams of carbon dyoxide CO2 and 5,4 grams of H2O. Determine the formula of the alkyne. Homework Equations CnH2n-2+[(3n-1)/2]O2=nCO2+(n-1)H2O The Attempt at a Solution x litres of Alkyne→n x 44grams of CO2 7,2...

I'm in my first year of university and will be taking a math, physics and an Earth science course. I'm not sure which subject to choose for my 4th subject however, at the moment I'm thinking either a second language (French or German) or chemistry. Would first year chemistry be useful for a...

So I'm an undergraduate student in Chemistry in my junior year and I recently transferred schools for a better science program. The one I was at was very, well, easy. Like toddler easy. I never went to class and I aced everything. Here, they're far ahead and it's much more rigorous. I was...

Hi, I am a high school sophomore and am thinking about what courses I need to register for my junior year. My advisor suggests that I take AP chemistry in junior year and AP physics in senior year. I wonder if I follow this suggestion, I won't have enough knowledge when I take the ACT test in...

1. The ionization energies of Rb and Ag are 4.28 eV and 7.57 eV, respectively. Calculate the ionization energies of an H atom with its electron in the same orbitals as the highest energy electrons in these two atoms. Another way of thinking of this is: what would the ionization energies of RB...

Author: Raymond Chang Title: Chemistry Amazon link: https://www.amazon.com/dp/0077274318/?tag=pfamazon01-20

Homework Statement 40 cm3 of a gas was exploded with 40 cm3 of oxygen (known to be in excess). Under the conditions used, only hydrogen and carbon monoxide reacted with oxygen. On cooling the mixture to room temperature, the volume was 51 cm3. On adding concentrated KOH, the volume decreased...

Author: Attila Szabo, Neil Ostlund Title: Modern Quantum Chemistry: Introduction to Advanced Electronic Structure Theory Amazon Link: https://www.amazon.com/dp/0486691861/?tag=pfamazon01-20

Author: Donald McQuarrie, John Simon Title: Physical Chemistry: A Molecular Approach Amazon Link: https://www.amazon.com/dp/0935702997/?tag=pfamazon01-20

Author: Donald McQuarrie Title: Quantum Chemistry Amazon Link: https://www.amazon.com/dp/1891389505/?tag=pfamazon01-20

Author: Jonathan Clayden, Nick Greeves, Stuart Warren Title: Organic Chemistry Amazon Link: https://www.amazon.com/dp/0199270295/?tag=pfamazon01-20 Level: Undergrad

I'm hoping for verification here that I'm not crazy on some very very basic chemistry questions. I've worked 7 problems on a practice test (the real thing is next Tuesday). Only 2 of my answers agree with the answer key. Here are the most dramatic examples. Please tell me I'm not crazy...

Complcated Chemistry Reaction - impossible?? Help :( My notes say: Step 1 is a 221 reaction. If peroxides are used in your version, then the anti-Markovnikov bromide is formed. If your version had only HBr, the the Markovnikov bromide is formeed. Step 2 creates organolithium or Grignard...

Our class doesn't use a textbook and our professor doesn't give out much notes. Just handouts with problems on it. So I wanted a textbook to accompany my studies but don't know which is the best/rigorious general chemistry textbook.

Question with part of answer: http://i.imgur.com/5Nki1SM.png More answer with questions: C-terminus should a carboxylic acid for both as the ester and amide will be acid hydrolyzed. The ester linkage should be more susceptible to acid because it is more reactive than the amide. This is because...

Author: J. D. Lee Title: Concise Inorganic Chemistry Amazon Link: https://www.amazon.com/dp/0632052937/?tag=pfamazon01-20 Prerequisities: Contents:

Homework Statement Attached Homework Equations Heat of reaction = Heat of formation of all products - heat of formation of all reactants The Attempt at a Solution 1.) It's 0 kJ/mol because it is. 2.) Every source agrees with 143 kJ/mol or 142.7 kJ/mol (which I've tried)...

Homework Statement I have a chemistry teacher who discourages students from asking questions (long story, but he's just not a good teacher). We have an online textbook, which fails to explain a lot when it comes to formulas. One thing I want to understand is what the different letters and...

Homework Statement Chloroethane, reacts with Oxygen according to the equation below: 2C2H3Cl + 5O2 → 4CO2 + 2H2O +2HCl How many moles of CO2 are produced when 3.0 moles of choloroethane and 3 mol of O2 are...

Author: Theodore L. Brown Title: Chemistry: The Central Science Amazon Link: https://www.amazon.com/dp/0130484504/?tag=pfamazon01-20 Prerequisities: Contents:

Author: Peter Atkins Title: Physical Chemistry Amazon Link: https://www.amazon.com/dp/0716735393/?tag=pfamazon01-20 Prerequisities: Contents:

"Guess the Mechanism" help! (Organic Chemistry) Homework Statement After identifying my reactants and products via spectral analysis, I am now tasked with figuring out the mechanism behind converting a diol into a ketone. Homework Equations The Attempt at a Solution The key to this appears...

Author: Robert T. Morrison, Robert N. Boyd Title: Organic Chemistry Amazon Link: https://www.amazon.com/dp/0136436692/?tag=pfamazon01-20 Prerequisities: No prerequisites Contents: User comments: https://www.physicsforums.com/member.php?u=331656: I can't really say much about...

Author: Jerry March, Michael B. Smith Title: March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure Amazon Link: https://www.amazon.com/dp/0471720917/?tag=pfamazon01-20 Prerequisities: High-School Chemistry Contents: User comments...

Hi, I have an exam tomorrow for atmospheric chemistry and I was just going over some past papers. In one it asks the following question, "What is meant by "Mean Free Path"? How is this relevant to atmospheric chemistry. My answer was as follows "The mean free path is the average distance a...

1. A vessel that contains a gas has two pressure gauges attached to it. One contains liquid mercury, and the other an oi lsuch as dibutyl phthalate. The difference in levels of mercury in the two arms of the mercury gauge is observed to be 9.50 cm.Given density of mercury =13.60 g cm-3...

Why does no temperature change occur while ice is melting? Specifially, when very little ice is left, how does so much water remain at 0 degrees Celcius? Is the energy transfer (of heat) to ice constant? Specifically, does the time range in an exponential manner for different sizes of ice to...

Homework Statement Okay i want to ask 2 questions. Question 1 Hyperstoichiometric compound Al3O has a vibrational energy spacing of 3.08x 10^-21J how many molecules are present in the ground state at 300k and 3000K Question 2 Calirimetric data for protein unfolding yielded following...

I am working my way through Ian Fleming's 'Molecular Orbtials and Organic Chemical Reactions' and I am having trouble with one of the exercise questions. (Ch2 Q1) It reads: Given that two pi bonds conjugated together have a lower energy than two separate pi bonds and a C-H bond conjugated with...

Hello, Since I can remember I have always dreamt of having an academic career and research. Theoretically physics seems very interesting to me and has always been my plan of what to pursue. The idea of knowing more about the world and discovering how it works is very enchanting to me. This...

I'm curious what your thoughts are on this program: https://uwaterloo.ca/science/current-undergraduate-students/majors-minors-specializations/medicinal-chemistry-co-op-only It's a new program at Waterloo. It sounds to me to be similar to pharmacology, but I was under the impression that...

I believe that the current chemistry curriculum has had a major increase in biological content in the past 10 years, and that this biological content has replaced valuable mathematical content. It used to be that the core classes of chemistry were, along with the basic math core of calculus...

My wife insists that pasta is not to be cooked with the lid on the pot. I reason that the cooking temperature must be fairly constant at the boiling point of water, so the energy required to cook the pasta can be reduced by putting a lid on the pot and turning the burner down just enough that...

I require some guidance on my career. My school offers a very vague stream sellection in the senior secondary section(Grade 11). I do wish to specialise in Physics or Chemistry as these subjects interest me quite a lot. To do so I must opt for the 'Science with Computer Science Group) at school...

Hi everyone! A couple of questions for you. So, I'm thinking about pursuing a career in chemistry research BUT I also really like physics, so I'm not really sure which to choose... -If I were to get a physics undergrad degree, could I move into chemistry? -If I were to get a chemistry Ph.D...

Homework Statement 50.0 mL sample of 2.0 10–4 M CuNO3 is added to 50.0 mL of 4.0 M NaCN. The formation constant of the complex ion Cu(CN)3 is 1.0 10^9. What is the copper(I) ion concentration in this system at equilibrium? The Attempt at a Solution I did a dilution and got the new...

Homework Statement Basically I'm doing a lab report where we place copper pennies in a solution of salt and vinegar. This should strip the copper oxide off the outside of the pennies, leaving the copper underneath shiny and looking "new". The problem is why we add the salt. Homework...

In a dish with the volume 1 litre we have 0.3 moles of nitrogen, 0.4 moles of hydrogen and 0.1 moles of amoniac. How many moles of hydrogen should we add to the dish so we can double the concentration of the balance for amoniac,if the temperature does not change? So I find the concentrations by...

Kp for the reaction H2+I2--> 2HI is 50.2 is 718 K. The ▲H (enthalpy) on standard conditions is 25 kJ mol^-1 .Use this information to find the enthropy of the reaction on 718 K...so I can findf free Gibbs energy from Kp,(in standard conditions) and therefore the standard enthropy..but how about...

1. A buffer is prepared by mixing a 100.0ml of a 0.100M NH3 solution with a 0.200M solution of NH4Cl and making the total volume up to 1.000L of water. What is the volume of the NH4Cl solution required to achieve a buffer at pH=9.5 Ka of NH4+ = 5.6x10^-10 The textbook tell me that the...

Hey guys, I hope this is the right spot to this. I don't want to get another infraction. I just got recently got out of my first physical chemistry class and am now thinking towards the second one. I'm wondering which book would be the best supplement to read over the break and help me get...

The reaction A+B ->Products is of second order related to A ,and of first order related to B.The reaction occurs on 298 K.When A=0.75 mol L^-1 and B=0,8 mol l^-1 the speed of the consumption of A and B is 0.00347 mol l^-1 min ^-1.What will be the speed of consumption of A and B after these...

Hello, how did chemists of the past know the weight of the elements to build up the periodic table without using new lab tecniques ? Have they transformed all the elements into gases and used Avogadro's law to obtain a relative atomic mass ? And how did they it was an element and not a...

Homework Statement Complete combustion of a 0.0150 mol sample of a hydrocarbon, CxHy, gives 1.680L of CO2 at STP and 0.810g of H2O a) what is the molecular formula b) what is empirical formula Homework Equations pv=nRt The Attempt at a Solution a) mol of co2: n=pv/Rt=1 atm *...

Reacton between the substances is A+B--> 2C where Pa=3 atm,Pb=2 atm.The reaction moves to the right until 70 percent of B has reacted and we have the equilibrum.FFind Pa,Pb,Pc and the constant of equilibrum Pa Pb Pc So in the beginning...

In 3000 K the constant of disintegration in the equilibrum of the reaction Cl2-> ( <-) 2Cl is 0.570 atm.In the equilibrum the reaction weighs 3 miligrams and is contained in a dish with volume 60 mL and the temperature is 3000 K.Find the total pressure. So I used p=n/V*R*T where n=m/M when M...

Hydrogen atoms are generated in an excited state where the electron occupies the 2p orbital. The excited sample of atoms then emits radiation that is directed to an unknown metal. The radiation ejects electrons with kinetic energy 8.77 x 10^-19 J. Given the data in the table below, identify the...