Homework Statement
Potassium chromate is an important compound of chromium. It is composed of K+
and CrO42-. Write the formula of the compound.
Homework Equations
positive charge + negative charge = 0
The Attempt at a Solution
I know how to do this problem by cross switching the...
In a famous experiment with a balloon and wool.
http://phet.colorado.edu/sims/html/balloons-and-static-electricity/latest/balloons-and-static-electricity_en.html
Initially the balloon and wool pullover have no ions.
I understand how positive ions are formed, that you apply energy to the...
Does there exist a fool-proof way of doing it?
I've scoured the forums, and I've already found this question, but the answers are not satisfying.
Here for example is exactly my question:
https://www.physicsforums.com/showthread.php?t=525291&highlight=polyatomic+ions
I've already...
Hi this may sound like a simple question but I'm trying to find out the relative abundance of hydrogen in its various forms in space:
H, H+, H-, H2, H2+, H2-
I'd like to know these for our stellar neighborhood involving the solar wind and also for interstellar space outside the heliopause...
Can atoms/ ions/ molecules behave quantum mechanically at bio-friendly temperature?
For example, cells in the human body needs around 37 degree Celsius to function properly. There are however some organisms such as Tardigrade ( which can survive for a few minutes at -273°C and for days at...
How does forming a bond between two ions lower the overall energy of the system? Also how would two hydrogen atoms form if there is proton-proton repulsion and electron-electron repulsion and only proton-electron attraction?
Homework Statement
Question: What kinds of ions may co-precipitate with a chloride ion? (List at least two).
This is a question for the theory section of my gravimetric analysis lab.
An unknown chloride salt is mixed into a solution. This solution is to be mixed with a certain quantity of...
A piece of unidentified element X reacts with oxygen to form an ionic compound with the chemical formula X2O3. Which of the following elements is the most likely identity of X?
A) Ba
B) Cs
C) In
D) P
E) Zn
I am doing exam practice questions...
I apologize if this is the wrong category,
Hello, this is my first time posting.
I loved physics concepts and theories when I was younger but after taking two physics classes in college I realized that I was struggling with the math and had to give up on my dream to become a theoretical...
I know that positively charged cation move toward cathode which is the negative terminal and the negatively charged anion move towards anode which is positive terminal
Why does in galvanic cell cations are moving toward cathode which is positively terminal?
And why in galvanic cell...
Homework Statement
Calculate the attractive force between a pair of Cu2+ and O2- ions in the ceramic CuO that has an interatomic separation of 200pm.
Homework Equations
E_A= -\frac{(z_1\cdot e)(z_2\cdot e)}{4\pi\cdot\epsilon_o\cdot r}
Where z_1 and z_2 are the valences of the two ion...
Energy of system of magnetic dipoles is
##E_H=-\mu_0 \vec{\mu}\cdot \vec{H}=-\mu_0\mu_zH##
why sign ''-''?
and ##\mu_z=-g_J\mu_Bm##
Again why ''-'' sign ?
##z## is choosen to be quantization direction, and along that direction is applied field ##H##.
What is the best way to separate ions in water? for example separating Na+ and Cl- ions from a sodium chloride water solution ( water is a ionizing solvent). is using magnets a best way or is electromagnets a best way or using Lorentz force(combination of electrical and magnetic force) a best...
Hi,
If we know the concentration of a salt (i.e NaCl) in a solute (i.e 0.1 M), is it possible to compute an average distance (in nm) of each Na vs/ Cl ions in this solute assumed mixed?
The image bellow is the PN junction under equilibrium.
I wonder why there are so many positive and negative ions in N and P types respectively.
For me, I think that these ions should only exist in the depeletion region not outside the region.
Thanks for help.
When we try to predict electronic configurations by the building up principle we add electrons to the d-orbitals before the p-orbitals for principal quantum numbers n ≥ 4.
What I don't understand is why, according to my textbook, we're supposed to remove electrons from np-orbitals first, then...
When a metal gets polarized it looks like this: http://postimage.org/image/bkdw8ttgn/
However, only the electron moves towards the positive ion. Why is this so? As both experience an equal force despite the different accelerations, shouldn't both the positive ion and negative electron come...
Homework Statement
"Calculate the force of attraction between a K +
and an O 2- ion whose centers are separated
by a distance of 1.5 nm."
Homework Equations
F = [ k (Z1)(Z2) ] / r^2
The Attempt at a Solution
Both valences are filled when K is a + charge and O is a 2-...
Cr3++?OH-→ Cr(OH)3
I think it should be 9 but the mark scheme says 3 but accept correct multiples because the 3+ charge has to be canceled by 3- and this has to produce 3 O
I need to know how to find the kinetic energy of ions leaving a charged plate. I figure I can find the electric potential energy, but all i know is the power being supplied to the plate and the plate's cross-sectional area. Any ideas? Thanks in advance!
Hi,What is a physical principle of measuring potential on membrane?
Or on body,if you measure potential of heart.I know,it sounds,like my question is nonsense.But I know,that voltmeter measure potential through free electrons.But for example if I have two clamp on body(eintohoven triangle),we...
1. If the statement ph=-log([H+] is true, then how come a solution can be acidic when carbonate is present? I have been told that even if carbonate does not accept H+ the solution will still be basic just by the presence of CO3(2-)? The confusion is this: ph only depends on [H+] then how come...
Hello everybody ,
We know it is possible to accelerate ions through electric field , this is in case of " Gas Ions " ...
But , when we put some salt ( i.e : NaCl salt ) in water , we get Na+ ions and Cl- ions also ,
If we made a circular chamber containing this solution and applied...
I knew while learning about electrolysis that if the ionic compound is molten it becomes free moving ions. If that is the case, what will happen if I continued heating till it reaches the boiling point so that the ionic compound evaporates?
Will it still be free moving ions?
Homework Statement
The biochemistry that takes place inside cells depends on various elements, such as sodium, potassium, and calcium, that are dissolved in water as ions. These ions enter cells through narrow pores in the cell membrane known as ion channels. Each ion channel, which is formed...
Homework Statement
What's the energy for transfer from
ε=1 to water with r=2.5Å
ε=1 to water with r=5Å.
Homework Equations
ΔG = (1/2)*(Z^2/r)*[(1/e1)-(1/e2)]
The Attempt at a Solution
ΔG = (1/2)*(Z^2/2.5)*[(1/80)-(1/1)]
However, I am stuck on the Z variable. Do I assume...
Hi guys, sorry as this is probably a silly question. This isn't homework, but it's something I'm confused about in my GCSE course.
If a lattice of ions can't conduct electricity when solid, then why can a wire (composed of these lattices (I think?)) conduct electricity?
The electrons in a...
First disclaimer: I do not want this for homework. I simply want an answer.
Nao, what I've seen, a single halogen can get into a 0 oxidation state combining with itself.
Now...could an inorganic ion have a total 0 by combining with itself? Could a SO4 join with another and create an...
Homework Statement
I'm having trouble approaching the following problem:
A research group is designing a device which will separate fast moving ions from slow moving ones. To do this, the ions are brought into the device in a narrow beam, so that all of the ions are going in the same...
Homework Statement
"Rank the following in the order of increasing absolute electronegativity: F, Li, Ti4+, P, H, C, Mg2+, Li+."
Homework Equations
The Attempt at a Solution
- I can rank neutral species no problem. Periodic table has that covered, and Pauling values are easy to...
I've just started a course on organic chemistry and the professor said some things which did'nt exactly make sense to me:
1) In a period, atoms are more electronegative as we go to the right. The more electronegative an atom is, the more stable it becomes.
2) In a group, atoms increase...
Homework Statement
Calculate the force of attraction between a Ca2+ and an O2- ion, the centers of which are separated by a distance of 1.25 nm.Homework Equations
Attractive energy (E) = -(A/r)
*The constant A is equal to (1/(4∏ε0))(Z1e)(Z2e)
where ε0 is the permittivity of a vacuum (8.85 x...
We have to determine in which of the following options, the first ion is more stable than the second.
1.
2.
3.
4.
5.
6.
Attempt at the question
1. Since in the first one, +ve charge is due to bonding, not deficiency of electrons.
2. First one can get lone pair from N.
3. N...
Dear all,
I have a question concerning a basic chemistry topic: atomic mass units. The current amu system defines 1 amu = 1/12 of a Carbon-12 isotope (about 1.66 * 10^-27 kg). Therefore, every other atom is assigned a amu value based upon its relationship to Carbon-12.
My question...
A device is used to measure the charge-to-mass ratio (e/m) of ions by accelerating them using an electric field described by a potential difference , and once they have acquired kinetic energy of known amount, they enter a uniform magnetic field. The particles move in a plane perpendicular to...
Hi,
I have a question about ions formed during ionic bonding.
Is this correct? "Sodium bonds with Chlorine to form Sodium Chloride (NaCl.) Sodium loses one electron & forms a positively charged ion and Chlorine gains one & forms a negatively charged ion."
If this is correct, when they...
In terms of neurons, the outside is more positive than the inside. Thus, a potassium ion trying to make an escape (due to it's concentration gradient) should be deflected/repelled back into the neuron. Those ions should be bounced back in when they reach close to the surface. But since not, this...
Greetings again forum!
I have a question about the influence of magnetic fields on liquids. Can a magnetic field ionize a solution? If so, please explain how. Thank you!
I'm not sure what: BaCrO4(s) + HNO3(aq) would yield. Would the product of this reaction be:
Ba(NO3)2(aq) + H2CrO4(aq)?
Or,
Ba(NO3)2(aq) + H2O(l) + Cr2O7(aq) ?
If so, why is this?
does forming OH- ions in water base solution absorb energy ?
How this mechanism works, from stable molecules to unstable ions?
is this reaction endothermic or exothermic?
Homework Statement
Calculate the wavelength of light needed to excite a Li2+ ion from the 4s to the 5d orbital. Report your answer with 3 significant figures.
Homework Equations
E=hc/lambda
lambda=hc/E
The Attempt at a Solution
I think that the above equations are supposed to...
Hi, I am trying to make a Magnesium source by curling up a tungsten wire with a block of Mg inside. Then by setting electricity to the tungsten wire, the Mg is heated and you get what out? Magnesium atoms? Magnesium ions?
Thanks a lot
/Carnot
What are the products of electrolysis of brine solution?
At cathode i know it will be hydrogen
But i am confused about the products at anode:-
Either water will get oxidised or chlorine. Considering the oxidation potential values - water should get converted to oxygen but practically...
Magnetic Field required two seprate to ions
Homework Statement
Consider a mass spectrometer used to separate the two isotopes of uranium, 238U3+ and 235U3+. Assume the ions enter the magnetic field region with a speed of 5.30X10^5 m/s. What value of B is required to give a separation of 0.6...
Homework Statement
The electrochemical cell:
SCE // CrO4 2- (x M) / Ag2CrO4 (s) / Ag (s)
is used for the determination of CrO4 2- . The standard reduction potential for the reaction:
Ag2CrO4 (s) + e = 2 Ag + CrO42-
is +0.446 V vs. NHE.
(b) Which of the...
Hello all,
I was reading about polyatomic ions for chem class, but in my textbook there was no description of how polyatomic ions are formed- it just states that they are a charged molecule. Are there any specific reactions that take place when a polyatomic ion is formed? For example, what...