Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds composed of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances.In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both basic and applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant chemistry (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the properties of the soil on the moon (cosmochemistry), how medications work (pharmacology), and how to collect DNA evidence at a crime scene (forensics).
Chemistry addresses topics such as how atoms and molecules interact via chemical bonds to form new chemical compounds. There are two types of chemical bonds: 1. primary chemical bonds e.g covalent bonds, in which atoms share one or more electron(s); ionic bonds, in which an atom donates one or more electrons to another atom to produce ions (cations and anions); metallic bonds and 2. secondary chemical bonds e.g. hydrogen bonds; Van der Waals force bonds, ion-ion interaction, ion-dipole interaction etc.
Hypothetically, if a chemist/physicist knew all the properties of hydrogen and all the properties of oxygen but knew nothing of water or its properties, would he be able to predict that combining 2 atoms of hydrogen and one atom of oxygen would produce a substance called water and its properties?
Hello everybody,
I am stuck with drawing resonance structures for different types of compounds. Do you know any tutorials or any methods to master drawing resonance structures? If yes, please be kind enough to drop some links and statements below. Thank you very much in advance.
Does the understanding and application of physics and fundamental chemistry is only required to be physicist? Or you have to be be equally apt in chemistry??
We all know that the state of matter can be changed by increasing temperature or by applying pressure. And, all of these, in some way lead to a change in the particles' speed. The speed of the particle decides the state of matter. So, if we were to throw an object at very high speeds, like 50%...
Why do we have to memorize the structures of all the nitrogen oxides? Isn't there any way to understand about the Lewis structures of all the nitrogen oxides and their weird ways of making bonds?
Homework Statement
In an organic compound "A" only C,H and O is present. 1.22g of A is completely burned and it gives 0.84g of CO2 and 0.54g of H2O. If the relative molecular mass of "A" is 123. Find the molecular formula of A.
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I have showed my attempt at solving this problem, but I think...
My chemistry teacher gave me this problem. I tried and tried, but I couldn't figure it out and the deadline is tomorrow. Please help me out here friends.
1. This is the problem :
In a compound which is made of element Y, weight percentage of Y is 72% and N( Nitrogen) is 28%. Also, 3 Y atoms...
We are learning the lesson about gases/gaseous states at our school and I couldn't help but wonder, why learn about IDEAL GASES... How do ideal gases help us to analyze about real gases?
Homework Statement
Homework EquationsThe Attempt at a Solution
I don’t have a clue on how to do the calculations. I know the equivalency point is at the steepest part of the derivative graph. Please don’t say just figure it out, I truly need help. I haven’t learned titrations in lecture yet...
Homework Statement
Solid sodium bicarbonate decompose when it's heated above 50 celsius. However, when it is dissolved in water interactions of components changes. So what happens when sodium hydrogen carbonate solution is heated? Does it release carbon dioxide when temperature is above 50...
Hello,
I am a bit confused re. solubility calculations.
Calculate the solubility of Pb(OH)2 at pH 10. Setting up the expression for Ksp:
Ksp = [Pb2+][OH-]2 = 8* 10^-17 (Ksp value from SI chemical data)
pOH = 14 - 10 = 4, i.e. [OH-] = 10-4.
8*10-17 = [Pb2+][OH-]2. Solving for [Pb2+] we get...
Hello
Being a professional physicist(Quantum field theory and HS theory) I'd like to learn chemistry for some reasons. I've already tried to find a nice Chemistry textbook but failed to find physicist friendly one.
My last class on chemistry was in high school like 11 years ago already, so my...
Published this week in the journal Science, researchers report that they have devised a eight letter alphabet for DNA and RNA:
The work builds off of previous work, which had expanded the genetic alphabet to six letters. The researchers call their eight-lettered nucleic acids "hachimoji,"...
Homework Statement
calculate the number of moles of potassium manganate required to neutralise oxalic acid.
2KMn)4- + 5H2C2O42-+ 16H+ --> 2Mn2+ + 10CO2 + H2O
Homework Equations
n = c x V
n= m/Ar
The Attempt at a Solution
Moles of oxalic acid = 5x10-4
Volumeol of KMnO4 = 0.01085dm-3...
Homework Statement
Kc = 4.15 x 10-2 at 356°C for PCl5(g) ↔ PCl3(g) + Cl2(g). A closed 2.00 L vessel initially contians 0.100 mol PCl5. Calculate the total pressure in the vessel (in atm to 2 decimal places) at 356°C when equilibrium is achieved.
Homework Equations
PV=nRT
Kp= Kc(RT)^change in...
Homework Statement
Kc = 1.37 for HI(g) ↔ 1/2 H2(g) + 1/2 I2(g). What is Kc (to 3 decimal places) for H2(g) + I2(g) ↔ 2HI(g)?
Homework Equations
Kc= Products/Reactants, Ice Tables
The Attempt at a Solution
I tried an ice table, but I’m not sure what to do with the Kc value I’m given when I...
Homework Statement
The Gibbs-Thompson relation provides a correlation between solubility and radius of curvature. Consider two spherical particles of radius r and R present in a solvent, with R >> r. The rate of dissolution of the smaller particles (the rate of decrease in its radius with time)...
Homework Statement
NaCl has a density of 2.16 g/cm3 and a surface energy of 2x10-5 J/cm2. Calculate the surface energy of 1 g of NaCl. Initially the complete 1 g is in the form of a single cube (of mass 1 g) and progressively broken into smaller cubes with sides of 0.1 cm, 0.01 cm, 10 μm, 1 μm...
Homework Statement
Aluminum metal dissolves in hydrochloric acid. What volume, in mL, of 1.58 M HCl is needed to completely dissolve 3.200 g of aluminum?(Hint: write the single-replacement reaction first)
Homework Equations
V[1]M[1]=V[2]M[2]
The Attempt at a Solution
I got the...
The enthalpy of formation equation:
ΔHƒ°reaction=∑Δhƒ°(products)-ΣΔHƒ°(reactants)
When using the enthalpy of formation equation you get:
-2010-((-394x3)+(-286x4))= 316Kjmol-1
However, this answer is wrong. On the mark scheme, the answer is -316Kjmol-1.
So I used the enthalpy of combustion...
Homework Statement
Homework Equations
Formula of Kp and Kc
The Attempt at a Solution
You will easily be able to identify that the reaction will proceed in the forward direction when some inert gas is introduced.
So,my question is that why won't the amount of chlorine formed increase in...
Hello,
I'd like to work in the above named center at the University of Georgia in Athens, Georgia under Dr. Henry Schafer. However, he's a professor in the chemistry department. I'm guessing if I go in the university as a physics graduate student I can't have him as a Ph.D advisor. However, is...
I'm a weak student in chemistry, by 'weak' I mean I lack some base I think. May please suggest some good books on inorganic chemistry? I want to study p-block, d- and f-block elements along with their important compounds and their preparation. Book should be concise as for me as a weak student...
I’ve already taken intro chemistry with a lab, and general chemistry 1. Unlike most universities, my college doesn’t require chemistry for physics majors. Should I take general chemistry 2? Would it really benefit me, or should I spend my time elsewhere?
Edit: I’m referring to the standard...
Homework Statement
Hello,
As part of my engineering orientation class, my team and I have to make a device that can keep a beaker of water warm. We have a list of materials we can and cannot use, but my team and I have decided on aluminum foil and maybe wood. We don't actually have to build...
Homework Statement
The relationship between pH and pOH, for pure water, at 25 ◦C is
14 = pH + pOH
What is the corresponding relationship between pH and pOH, for pure water, at 70 ◦C?
Homework Equations
Le Châtelier's principle?
[H+][OH-] = 10-14
[10-7][10-7] = 10-14 (25 ◦C)
[10-n][10-m] =...
Homework Statement
Which one is more reactive, CO2 or NO2?
Homework Equations
The Attempt at a Solution
I drew the Lewis structures of these species and found there is one delocalized electron in NO2, so I think NO2 is more reactive.
Am I correct?
Homework Statement
The question's in the screenshot attached.
Homework EquationsThe Attempt at a Solution
I don't know why (B) would be right. I feel like since for Mg's second ionisation energy, it is going from Na to Ne, and Ne is another energy level, Mg's 2nd ionisation energy should be...
Homework Statement
There are four things to be calculated:
-pH of 0.00196M solution of HCl in water, without taking ionic strength into account,
-The same thing but taking ionic strength into account
-pH of 0.00196M solution of HCl in Na2SO4, without taking ionic strength into account,
-And...
Homework Statement
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Which is more stable cyclobutane or cycloheptane?
Homework Equations
[/B]
[(n-2)180)]/n = angle
The Attempt at a Solution
[/B]
So the closer the angle is to 109.5 the more stable (except for cyclopentane vs cyclohexane).
n = number of carbons
[(7-2)180)]/7 = 128.57...
Dear friends, I've been having trouble focusing on chemistry with all these boring teachers I get at school. I want some help to increase my interest for chemistry so that I can research about chemistry alone at home. Dear friends, what are the ways I can think of chemistry and how should I...
Is melted bismuth safe to wear pretty much 24/7 around your neck ? I don't want to get a super low radiation hyper bug cancer fungus to appear after 30 yrs...
(It touches your skin permanently unless you're running ofc)
On top of that, can I smelt bare bismuth (99%) in my kitchen or should I...
Homework Statement
How to draw it?
Can someone tell me the electronic configuration of the chromium atom in tris( acetylaceato)chromium( III) please
Homework Equations
N/A
The Attempt at a Solution
N/A
Homework Statement
Suppose that, for reaction 4, you could not find the bottle of 7 M H2SO4 so you added 5.00 mL of the 1.00 M H2SO4 instead. How would this impact your final yield of Copper. (Show with calculations how this would impact the limiting reagent.)
Homework Equations
CuO(s) +...
Hey.
If i carry out electrolysis of saturated sodium bicarbonate solution with lead electrodes, will the lead electrodes will dissolve to form lead carbonate (or basic lead carbonate if temperature is higher) or the lead ions will migrate from anode to cathode and deposite there?
I think that...
Hey i am currently doing my bachelor's degree in Science. I have a biology background but i am very much into chemistry, specially organic chemistry and conceptual physics. I hope all the great people here will help me with my queries and i would also be so nice if I could be of help to anyone.
Homework Statement
What is the reaction occurring in
H2O + SO3 -> H2SO4
2. The attempt at a solution
Sorry, if this is dumb, I was confused about this question because I think its synthesis but I thought it only worked with elements? (Element A + Element B = Compound AB)
But then with this, I...
Homework Statement
Lead (II) nitrate + manganese (IV) iodide -> _______
2. The attempt at a solution
So I think I know how to do this
2 Pb(NO3)2 + MnI4 -> 2 PbI2 + Mn(NO3)4
I'm just a bit confused because with single displacement you have to check the activity series? And so I'm not sure if I...
Generally speaking, would it be better to pair a CS/Math minor/minor or minor/major (respectively) with physics or an additional natural science major (e.g., biochem, biophysics, chemistry) with physics?
I plan on going to grad school to either pursue a physics Ph.D. or a master's in...
I want to use small molecular - preferably CNT - "antennas" to produce THz signals to monitor activity in biological systems. After some googling, I've been reading things like "absorption spectra", "energy bands", "spectroscopy", as well as a bunch of antenna-science related jargon... I need...
Hi all, I have a question about this exercise:
Which is the best option of pH for electrophoresis separation of two peptides with isoelectric points of 10.3 and 7 respectively? The given options of pH are 3,8 or 10.
I've thought that if pH is more than 7, then, there will be positive charge...
To sum up the current biggest stress of my life into a question: do you recommend that I stay in a biology/chemistry-based research program or pursue proof-based math courses?
I am a freshman physics major at a good research university. I was invited into a very difficult program for "future...
Homework Statement
You may have noticed that water sometimes drips from the exhaust of a car as it is running. Is this evidence that there is at least a small amount of water originally present in the gasoline?
Homework Equations
not sure if there is one.
The Attempt at a Solution
I'm not...
Homework Statement
The spectrum shows the series 3p - nd, n = 4 - 7 in Na as well as the resonance line 3s - 3p, with the experimental vacuum wavelengths in Å.Calculate the quantum defect for the nd ##^2D## n = 4-7 terms. Estimate, as accurately as possible, the wavelength for 3p - 8d. The...
Chemistry World (a magazine published by the UK Royal Society of Chemistry) is reporting that YouTube seems to indiscriminately be taking chemistry videos off of the site and banning the creators of those videos...
Basically, the F block is a series in the periodic table that consist of elements that are artificially synthesized. My question is, why were these elements synthesized? What was the need of synthesizing such elements?
Homework Statement
The ratio of KMnO4 to I2 is given by
2 MnO4 - + 16 H+ + 10 I - ⇌ 2 Mn2+ + 5 I2 + 8 H2O
the ratio is 2:5
- The ratio of I2 to S2O3
2- is given by 1 I2 + 2 S2O32- ⇌ 2 I-+ S4O5 2-
the ratio is 1:2
therefore n(S2O3 2- ) = n(MnO4 - ) x 5
Homework Equations
Why the mole of...