Chemistry Definition and 993 Threads

Hey! I have a question regarding this question that I have to answer. It is about the kinetics of a substance X whose product is 2Y. It is in Swedish and here is the translation: The absorbance of a 0,030M-solution of X was calculated with the help of a Spectrometer. The Spectrometer was...

For example: If I isolated (in a perfect vacuum), one Magnesium atom and one Oxygen atom, and they are close to each other, will they make a bond by themselves, with no outside energy? Does this work with any combinable pair of atoms, and what other pairs of atoms would make a bond by...

Hi, I am trying to simulate in 3D a bunch of chemical reactions. Some of them are complex and I would like to be able to just spawn the elements and molecules and watch them collide to see what happens. Is their any free software to do this?

AgBr →Ag + Br2 This reaction takes place in presence of light energy, but why only light ?? Why not electricity, heat or any other forms of energy?

Homework Statement :[/B] The density of a 2.05 molar solution of acetic acid is 1.02g/ml. The Molality of the solution is: (a) 1.14 mole/kg (b) 3.28 mole/kg (c) 2.28 mole/g (d) 0.44 mole/kg Homework Equations :[/B] The Attempt at a Solution :[/B] I tried it out very simply using unitary...

Homework Statement http://i.imgur.com/rNoD3Lm.png Homework Equations Conservation of energy in an enthalpy cycle The Attempt at a Solution I can't complete draw the enthalpy cycle! http://upload.lsforum.net/users/public/l50630IMG_4306s76.jpg Can anyone help me? Thank you very much!

Homework Statement https://holland.pk/uptow/i4/1ca04ddf7c25f6c63e307720c34a4ff3.png Homework Equations First principle of thermodynamics: E=q+w The Attempt at a Solution E=q+w=-17+21=4kJ>0 ∴Endothermic (absorb heat from surrounding) (a) false (from surrounding to the system) (b) false (does...

Hello all, So I've finished my first year of classes. Since my school has a credit window for declaring engineering majors, I need to lock in my life-long career decision. I definitely want to stick with engineering, but I was curious if ChemE is the right one for me. From what I've read, the...

I think this is a chemistry question... Due to the Montreal Protocol (https://en.wikipedia.org/wiki/Montreal_Protocol) and subsequent phase-out schedule for all the “conventional” refrigerants, many/most of us in the HVAC service industry are consequently working with “interim” alternatives for...

Homework Statement So LG is on 2° position, and you have a hydride shift. So you form one product on 2° and one product on 3°. Which product will be major which will be minor? Homework Equations none. The Attempt at a Solution I know hydride shift will be more major than a methide shift...

Homework Statement If the text is too small, it reads: 'A student measured the pH of water at various temperatures using a pH meter and obtained the following results: (table showing pH decreasing as temperature increases) The student was unsure whether the results were accurate or if the pH...

So far, I have taken General Chemistry I and II, and Organic Chemistry I. Out of these classes, only General Chemistry I seems to make use of the periodic table, but it is mostly just going through the basics of the periodc table. Not so much in Gen Chem II or Orgo I. I mean they give it to you...

Homework Statement Hi, following Wednesday I'm going to produce ammonia in the lab at school but we have 3 questions we have to solve beforehand. The first one asks the global reaction being ammonium chloride reacting with calcium hydroxide to form ammonia, water and calcium chloride, but it...

I'm starting a chemistry course in a few months & I'm a little nervous as my math skills aren't that good. Could anyone tell me which type of maths I'll be using in the course based on the modules that I need to complete? I'll like to work on my math skills in advance. Thank you :). Here's a...

I just had a lab, and the results really aren't adding up to what i expected. And this is specifically about simple distillation, not fractional distillation. Lets say i have a solution of two liquids, one's boiling point is 90°C and the other is 110°C, a 20°C difference which is pretty close...

I'm trying to solve one of the problems in my textbook (Atkins Physical Chemistry) and I just can't get it out. Here's the problem: "The data below apply to the formation of urea from ammonium cyanate. Initially 22.9g of ammonium cyanate was dissolved in enough water to prepare 1.00 dm3 of...

Homework Statement Predict the major product and type of reaction mechanism (E1/E2/SN1/SN2) Homework EquationsThe Attempt at a Solution Could someone just double check my work for this? From top to bottom I got: E2, E1, SN1, E1

Homework Statement Predict major product and what type of reaction mechanism Homework EquationsThe Attempt at a Solution Top Problem: So the Bromine is a good leaving group, and is in the secondary position so you cannot rule out anything right away. The nucleophile is charged, so it will be...

I want to refresh my skool-achieved knowledge about Chemistry, and then I want to move in direction of Chemistry of Computer Systems, Chemistry of Brain, Chemistry of Neurons, Chemistry of DNA, etc. Any good advises about literature? For now I have this book in digital form - "Introductory...

I am interested in breakthroughs in technology, physics and chemistry. Every once in a while I will post a challenge question to see if anyone has ever been confronted with this challenge or has experimented in that field.

Homework Statement The complete combustion of methane is represented in the following equation: CH4(g) + 2O2 -> CO2(g) +2H2O(g) +802.5 kJ Assume that natural gas is essentially methane. The emission level of Carbon monoxide, CO(g) from the burning of natural gas is 19.14kg/MJ of energy...

What is the nuclear binding energy of N-14 in joules per mole of nuclei? The mass deficit is 0.11278. Atomic mass is 14.00307. Total mass is 14.11585. I keep getting stuck after converting and substituting it into the equation. First I converted the mass deficit into kilograms. 0.11278 =1.1278 ×...

A lab mate and I are discussing how to properly interpret LCMS results and coming to different conclusions. We are taking a solid food sample and extracting it with 50:50 acetonitrile/water to determine the concentration of melamine in the food sample. Standard solutions were made that range...

I'm in Cegep in Canada, which is basically between high school and University. I strongly liked chemistry in the past, and I was very strong. Last semester, our chemistry class was Chemistry of Solutions (covering equilibrium, kinetics, acids-bases, etc), and this semester we have to take...

What is the meaning of the appearance of the following species in a combustion: -OH -H2O2

Homework Statement A classmate says "Since there are 2n^2 electrons possible in each energy level, and the atom with the greatest number of electrons has 118 electrons, that must mean that u is the highest possible value for n, because a value of 7 gives 2n^2 = 98 nad a value of 8 gives...

Homework Statement A.[/B] Someone is walking outside when the temperature of the air is -10°C. The metabolic rate of walking is 140 Cal/m2hr, and the usual muscle efficiency (20%) applies. They are completely covered by clothing with a coefficient of thermal conductivity of 0.36 Cal-cm/m2hr...

Hello How is this degree? Is it hard? Is this combination is good? I would like to do a PhD on physics and for now I know the basics of C++ programming and in the future I want to expand my knowledge with Microsoft courses or something like that.. Thanks!

Homework Statement Fe2+and Cr2O72- react as follows: 6Fe2+ + Cr2O7 2− + 14H + >>> 6Fe3+ + 2Cr3+ + 7H2O. The equilibrium constant for the reaction is 1×10^57. Calculate the equilibrium concentrations of the iron and chromium species if 10 mL each of 0.02M K2Cr2O7 in 1.14M HCl and 0.12M FeSO4...

Could someone explain to me why the ring structures in this photo are diastereomers? From looking at them, I see a plane of symmetry, and no chiral centers so I'm unsure how they're diastereomers without have R/S characteristics

Can we measure 'absolute entropy' of a system. Also can entropy become zero at 0 kelvin.is it possible only theoretically?

We were doing O2 estimation by Winkler's method The procedure and reactions involved in this experiment are: Carefully fill a 300-mL glass stoppered bottle brim-full with sample water. Immediately add 2mL of manganese sulfate to the collection bottle. Add 2 mL of alkali-iodide reagent (NaOH +...

I've recently picked up chemistry as a hobby. It's very educational while also being entertaining. I've started an element collection, and made some simple compounds as well. The thing is, I get asked quite frequently what is the practicality of hobby chemistry, and I have trouble providing a...

Hi all, sorry if this is a little emotionally charged but I am a second semester sophomore chemistry major and I am very hard on myself about the grades I received in my major. First of all, I took the hardest possible general chemistry class as a first semester freshman because I wanted to be...

Homework Statement In this lab we are going to be given a mixture containing sodium chloride [NaCl], silicon dioxide [SiO2], Iron filings [Fe], and calcium carbonate [CaCO3] The goal of the lab is to use separation and measurement techniques to determine the percent by mass of each specie in...

Homework Statement Hydrogen peroxide can be prepared in several ways. One method is the reaction between hydrogen and oxygen, another method is the reaction between water and oxygen. Given the ΔG°rxn values for each reaction, which method (reaction 1 or 2) requires less energy under standard...

Hi! I want to clarify what will happen if you mix two acids. One is stronger and One is less stronger. What will be the pH level result? for example if the acid is the juice from lemon which is at 2.0 be mix with orange ph level of 3.0, will it be greater than less than 2.0? or will it be 2.5...

In my labs we use hot plates with a 0-10 temperature knob. The hot plates don't have a temperature monitor, so i have no idea how hot each number can increase it or how hot it is at the time. Sometimes i have labs where i have to heat something to more specific temperatures or else the reaction...

I would like to buy a textbook to learn about this subject, and I was wondering if anyone had any ideas on what to buy, thank you very much for any responses. Not too expensive please. I am teaching this to my self if matters. Not part of university or other courses.

1)When Mg is burned in air,a mixture of MgO and Mg3N2 is produced.If 3,6g of Mg produces 5,7g of mixture,what is the percentage by mass of each compound in the mixture? 2)A solution of an acid having the formula H3NSO3 is prepared by dissolving 9,7g in water and making up the solution to...

Homework Statement The energy operator for a time-dependent system is iħ d/dt. A possible eigenfunction for the system is Ψ(x,y,z,t)=ψ(x,y,z)e-2πiEt/h Show that the probability density is independent of time Homework Equations ĤΨn(x) = EnΨn The Attempt at a Solution [/B] I understand the...

Homework Statement [/B] I had an inorganic lab this week which involved making VO(acac)2 from VOSO4⋅xH2O. In order to calculate the percentage yield, I need to work out x, that is, the number of water molecules coordinated with the vanadyl sulfate n-hydrate before the reaction. I'm stuck...

So I am doing a chemical simulation of titans atmosphere and I have potentially 1000 data files to sort through to retrieve concentration values written in Double format. The issue is that each chemical has its own line with well over 80 columns (1993 currently, though it is subject to...

Knowing Ks=6⋅10−38 for Fe(OH)3 in neutral solutions, calculate the minimum pH of an acidic solution in order to completely dissolve 10 mg of Fe(OH)3. Data: Volume = 0.1 L. I set out the equation for the equilibrium constant. having first calculated the concentration or iron ions (9.35899*10-4...

I am a sophomore chem major taking my second semester of organic. I plan on going to grad school. I took calc 2 last semester but calc 3 is not offered next semester so that is sadly out of the question. I can't take classical mechanics without calc 3 and I've already taken prob. and stats. No...

Homework Statement The total pressure of a mixture of oxygen and hydrogen is 1.00 atm. The mixture is ignited and the water produced is removed. The remaining gas is pure hydrogen and exerts a pressure of 0.34 atm when measured in the same volume and at the same temperature as the original...

I am so stressed right now and am on the verge of a nervous breakdown. My chemistry homework is just really confusing and I need to pass this class, could someone please help me out? I need to hand this in tomorrow and I have already answered the questions myself but I feel like my answers are...

Homework Statement Write separate equations for each potassium salt (KH2PO4) dissolving in water and for the ionization reaction of the weak acid anion that each of these salts contains. Homework Equations None The Attempt at a Solution I just needed to clarify when it dissolves in water do...

Merry Christmas everyone! I have a question and I want some honest answers. So this semester I took Organic Chemistry 1 and Calculus 1. I both passed but with a D, sadly the courses won't transfer to my school I want to attend in the future (waiting for a response from the schools I applied...

Hey guys! So I have this chemistry problem which I'm finding very difficult. QUESTION: You have an unknown triprotic acid, H3X, and have titrated it with 22.53mL of NaOH. The pH of the unknown solution is 2.04 and the concentration is 48.028g/2L. While the concentration of the NaOH is...