Questions tagged [conductivity]
A material's ability to conduct electric current or thermal energy by any means.
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Electrical conductivity of graphite
On this Wikipedia page, the electrical conductivity of various materials are given in the third column ($\sigma \text{ (S/m) at 20}^\circ \text{C}$). I am interested in the entry for Carbon (graphite)...
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Is "Sulfuric acid... makes a poor electrolyte... very little of it will dissociate into ions" really true? What does that actually mean?
While researching chromate conversion coating for edits to this answer in Space Exploration SE, I came upon the following passage in Corrosion Resistance of Stainless Steel to Sulfuric Acid
Sulfuric ...
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Conductivity as a function of acid concentration
I have conducted an experiment measuring the conductivity of both hydrochloric acid and sulfuric acid in solution respectively, with varying concentration. Wikipedia as well as a question on the site ...
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Why is it that the least reactive metals are the best electrical conductors?
Silver, Gold and Platinum are amongst the best conductors of electricity, but also the amongst the most unreactive. Since electrical conductivity depends on the number of delocalized electrons (along ...
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Choice of doping elements in semiconductors
In a typical semiconducting material, we start with silicon (group IV) and introduce atoms of group V or group III depending on whether we are constructing an n- or p-type semiconductor respectively.
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Why does the graph of the electrical conductivity of sulfuric acid/water solutions have this knee in the ~85%-~92% range?
This answer to an earlier question regarding the electrical conductivity of sulfuric acid provides a graph showing the conductivity of sulfuric acid/water mixtures ranging from 0% to 100% sulfuric ...
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What is the difference between molar conductance and molar conductivity?
I'm learning (or at least trying to learn) about electrochemistry, but a major obstacle to that, is that different books I refer use different terms for the same symbols. So in a last ditch attempt to ...
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How does conductivity work for non-redoxed ions?
Related (very similar, but here I want a mechanism) https://physics.stackexchange.com/q/21827/7433
By the Kohlrausch law, all ions contribute to the conductivity of an electrolyte.
Now, as I ...
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Does an electrically conductive gas exist at room conditions?
As I know, the gases are insulators, because their particles are mainly electrically neutral, and thus there is no movable charges in them.
But maybe it shouldn't be always so, for example if a gas ...
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Why is copper a better conductor than iron?
Metals are good conductors as the electrons in their outer shell are loose and can plunge out of the atom with the application of the slightest force (voltage).
Silver is the best metallic conductor, ...
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Is there any electronic component to water conductivity?
Answers to Decrease in temperature of a aqueous salt solution decreases conductivity indicate that the electrical conductivity of salt solutions arises from the mobility of ionic species and therefore ...
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Why are ionic compounds bad conductors of electricity in solid state?
I understand the fact that ionic compounds are good conductors of electricity in molten state. But why aren't they good conductors in solid state. Cannot ions vibrate about their mean position and ...
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Does the delocalization of p-orbitals ensure conductivity?
For example, polyacetylene is a conjugated system, i.e. with de-localized p-orbitals, but accroding to Chiang et. al. (1977) polyacetylene is semiconducting, and becomes conductive only when doped ...
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Why do we do electrolysis and electroplating using warm electrolyte?
This is a pretty basic question, and I know it has something to do with conductivity, but I'm not quite sure how they are related.
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Why are isotopically pure diamonds 50% more thermally conductive than other diamonds?
A laboratory grown type-IIa diamond (no nitrogen defects) has a lambda of $\pu{1800-2200 W/mK}$, but an isotopically pure diamond of $\ce{^{12}C}$ can have up to $\pu{3320 W/mK}$.
Why are $\ce{^{12}C}...
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Are there compounds more conductive than Silver (Ag)?
Silver is the most electrically conductive element on the Periodic Table. However, I am interested in knowing if there are any compounds (combinations of elements) that would be more conductive than ...
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Why conductivity of electrolyte decreases on dilution, but molar conductivity increases?
I learnt that on dilution of an electrolytic solution, it's conductivity decreases. However, there is an increase in the molar conductivity of the solution. The book explained the reason by comparing ...
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How to derive the conductivity titration curve which accounts for salt formation
I derived an equation that gave me the volume of base required to get a certain $\mathrm{pH}$:
In a titration between a weak acid $\ce{HA}$ and weak base $\ce{B}$ (adding base into acid solution) the ...
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How strict is the "to excite electrons the energy must equal the energy state difference" fact?
We are always told that to excite an electron from one state to a higher energy states, for example from the valance band to the conduction band, the energy must equal the energy difference between ...
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Can dust conduct electricity?
Just out of curiosity, can dust conduct electricity? The source of dust varies, is there any form of dust that can conduct electricity?
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How to relate the conductance of an aqueous electrolyte to its conductivity
In this answer on Physics Stack Exchange, the author states that conductance $G$ is related to conductivity $\sigma$ by $$G = \sigma\frac{A}{l}$$
where $A$ is the cross-sectional area perpendicular to ...
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How exactly does electrolysis occur if the molar conductivities of cation and anion are different?
I'm having trouble wrapping my head around Kohlrausch law of infinite dilution and molar conductivities in general.
For a salt $\ce{AB}$ the molar conductivity at infinite dilution can be expressed as ...
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Why does the specific conductivity against concentration curve for NaCl curve more than KCl?
I understand why KCl has a higher specific conductivity than NaCl.. but I dont understand why the curvature is more significant for NaCl (KCl is a straight line). Ive provided a picture of this here, ...
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Why is the rubber tip of my capacitive stylus no longer conductive?
In 2014, so eight years ago, I bought five styluses from China. Cheap stuff obviously. They worked fine while I used them, but soon after they were just left in a drawer. Last night I realized that ...
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Mathematical Expression for Limiting Molar Conductivity [closed]
I have been fiddling around with the theory of electrolytes, specifically molar conductivity, and ways of calculating limiting molar conductivity $\Lambda^0$.
I was able to come up with the following ...
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Conductivity measurements of demineralized water - Unexpected results. Looking for explanation
I'm trying to measure the conductivity change of demineralized water over a few days. But I get results I can't explain.
Setup
This is the circuit and cell I'm using:
Where $R_x$ is the ...
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What solvent would have the fewest ions?
We know that water auto-ionizes (to a rather small extent).
My question is which solvent would have the fewest ions (or at least fewer ions than water).
I'm thinking that perhaps some kind of ...
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Decrease in temperature of an aqueous salt solution decreases conductivity
Why does the conductivity of a water solution drop as the temperature decreases?
How are these two related?
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Examples of electronically conductive foods?
There are many foodstuffs that are ionically conductive (for example, anything moist and salty). What about foods that have a high electronic conductivity?
The only thing I can think of would be ...
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Formation of Bands in Semi-Conductors
At school, we are learning about semi-conductors and their applications in modern electronics. One of the features of semi-conductors is that there is a small energy gap between the valence and ...
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Behaviour of element 111
Is element 111 considered to act as an eka-aurum?
Being under the same column of group 11, which usually provides enough evidence for correlation of properties for an eka-element, would this element ...
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Kohlrausch Law and conductivity
Im writing up a lab report at the minute and part of it concerns ions in solution and how they affect conductivity. I've been doing lots of reading and I think ive got the grasp of most of it, but its ...
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If liquid hydrogen fluoride autoionises, how can it be an insulator?
According to Wikipedia, one of the last major hurdles in the isolation of elemental fluorine was the need to mix hydrogen fluoride with another substance in order for its electrolysis to be possible (...
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Why is fullerene 60 an insulator while graphite is a conductor?
Graphite is good conductor of electricity because one carbon atom is bonded only three carbon atoms, which enables the presence of free electrons. In fullerene 60 the carbon atoms are also bonded to ...
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Why does the conductivity of a LiOH solution decrease when boric acid is added?
If I start with pure water and add $\ce{LiOH}$ the conductivity of solution increases. However, if I then dissolve boric acid in the same solution the conductivity falls. I would have thought adding ...
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What is the electrical conductivity of pool water?
What is the electrical conductivity of pool water? I tried to find some information, unfortunately without success. I need to know it to make an underwater electronic project.
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Why do gases under low pressure conduct electricity?
In J. J. Thomson's cathode ray experiment, he used a discharge tube in order to make the gas inside conduct electricity.
Why do gases under low pressure conduct electricity?
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Can all water soluble ionic compounds conduct electricity?
I'm taking a first year university chemistry course, and I am reading a lot of contradicting things. Some people say that ionic compounds that are soluble in water are always electrically conductive, ...
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Are there any trends for electrical conductivity?
Which element has the greatest electrical conductivity?
(A) $\ce{As}$
(B) $\ce{Ge}$
(C) $\ce{P}$
(D) $\ce{Sn}$
I am unsure of how to approach this problem. Is there some sort of trend for ...
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How can I calculate the molar conductivity of a solution with multiple solutes?
I'm running an experiment mixing 2 different solutions, $\pu{5 mL}$ of $\pu{0.1 M}$ $\ce{NaCl}$ with $\pu{5 mL}$ of $\pu{0.1 M}$ $\ce{KCl}$. I am measuring the conductivity of the total solution in $\...
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Molar conductivity calculation in a titration curve
At an exam for analytical chemistry, I was asked to calculate the molar conductivity of a solution for an ongoing titration. I just solved it the way our professor showed it to us but I have some ...
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What is A in the following equation
This equation describes the total current in bulk solution in a battery caused by migration in the electrolyte.
Then the source says what A is: In the bulk solution (away from the electrode), ...
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Negative Ohm reading from a Electrochemical reaction?
The purpose of my experiment is to determine which salt is the best electrolyte. The setup is a tarnished spoon (Ag2S) is placed on top of thin plastic pieces that separate it from a container coated ...
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Linearity of electrochemical cells and electrical conductivity measurement
I've measured the output signal of a few commercially available conductivity meters and was surprised to see that the signal was typically a square wave of amplitude in the range of 1.5 to 6 Vpp (peak-...
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Why is ruthenium dioxide a conductor while titanium dioxide is an insulator?
Ruthenium dioxide has the same crystal structure as rutile (titanium dioxide), and the metal atoms are in the same oxidation state. Yet ruthenium dioxide is a metal-like conductor (its resistivity is ...
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Further reading on photoconductivity of hemoglobin
I recently ran into this paper which describe experiments that confirm that hemoglobin is photoconductive. Finding this fact as incredible, I wanted to read up more on photoconductive properties of ...
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Conductivity of electrolyte solution
I found a relationship online between the conductivity of electrolyte and current.
$$i = F \sum_i z_i N_i = F^2 \left( \sum_i z_i^2 u_i c_i \right)\nabla\phi = -\kappa\nabla\phi \qquad \kappa = F^2 \...
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Would a quarternary ammonium electride conduct electricity?
If suppose, I crystallised a quarternary ammonium electride could this conduct electricity similar to a metallic conductor? Metals have lattice atoms as charged metal ions are a sea of electrons. This ...
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Why does Ga improve conductivity of Ge?
This is for my AP Chemistry course and the question is:
Which of the following elements is important in the semiconductor industry to improve the conductivity of Ge?
K
Ga
Al
Mg
It seems like any of ...
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Vacuum good inside a box?
I have no clue whatsoever about Chemistry on a academic point of view.
We wish to transport some goods.
Let's say we vacuum some of those goods, by doing like so:
We place those goods on a box, we ...
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