Questions tagged [elemental-analysis]
The science of determining the elements a compound is made of or deriving the sum formula thereof. Can be applied both to practical and theoretical questions
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Chemical Composition of NMC cathode in lithium ion battery
I am working with lithium ion batteries having the cathode material as NMC i.e. LiNixMnyCozO2, wherein x + y + z = 1. The proportion of Nickel, Manganese and Cobalt in the cathode varies, but mostly ...
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Is it safe to touch salts given to you for analysis? [closed]
In our chemistry practical paper (High school level), Inorganic salt analysis is one of the questions asked. We are given a petri dish with a sample of salt and are asked to find the cation and anion ...
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Is it possible to obtain the amount of air required for a combustion analysis?
I'm not very sure if the required amount of oxygen (I assume) can be found by only knowing the amounts of the produced subtances after a combustion.
To illustrate this I found this problem:
$1.14\,...
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Do the procedure used to find the empirical formula from combustion analysis be extended in other cases when is not specifically mentioned?
The situation is as follows:
A sample of $\pu{19.40 g}$ from a certain compound consisting only in $\ce{K, Cr}$ and $\ce{O}$, receives a treatment. This gives $\pu{7.6 g}$ of $\ce{Cr2O3}$ and $\pu{...
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What does it mean to calculate "weight of SiO2 in the form of Si"?
This is with reference to the typical mass balance problems in iron making. Whenever we are asked to mole balance $\ce{SiO_2}$ it is treated this way:
$W_{\ce{SiO_2}}$ from iron ore + $W_{\ce{SiO_2}}$...
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SO3 in wood ash
I have seen several sources note that wood ash typically contains 3–4 % $\ce{SO3}$ by weight. My question is, why would ash have any $\ce{SO3}$? $\ce{SO3}$ boils at 45 °C, so it should have all boiled ...
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What instrument is used to detect heavy metals? [closed]
If i have blood sample, organ tissue sample or food sample, what analytic technique is used in laboratory to detect the ppm levels of heavy metals? What electronic intrument they use?
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How is hair tissue mineral analysis performed?
This might be a mixed chemistry / physics question, but I've always wondered what methods were used to precisely determine the levels down to trace amounts of all minerals in human tissues. I know ...
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Is barium sulfate soluble in dilute mineral acid?
I have read that $\ce{BaSO4}$ is soluble in $\ce{HCl}$ , but I am not sure whether this works for dilute acid as well.
The reaction is -
$\ce{BaSO4 + 2 HCl ->BaCl2 + H2SO4}$
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Removing sodium borate for the test proving thiocyanate ions
I've just learned that when carrying out the identification test for thiocyanate ions borax can induce a false positive and therefore needs to be removed. I couldn't find the answer on google so I'm ...
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Sodium Sulfate vs Sodium Sulfite
I recently took a test and one of the questions was:
Which procedures will allow a student to differentiate between solid sodium sulfate and solid sodium sulfite?
I. Make solutions of each ...
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How can I Identify Elements in Objects? [closed]
Since all objects on earth are composed of elements, how can I identify the fundamental make-up of objects such as trees, glass, bricks, wood, plastic, shoes, and other entitys?
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Taking a procedure for ICP and adapting it to use with AAS
I was reading a paper regarding metal detection and they gave their procedure for an acid digest of a soil sample which was then analysed by ICP-OES.
They used nitric acid, hydrogen peroxide and ...
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Combustion analysis methodology question
I am questioning the answer key of an exam question my chemistry professor has given, because I think there is a flaw in the methodology of the exam answer. I have worked out my solution using my ...
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What happens to chromium (as Cr2O7-) in the plasma of the ICP?
I have recently been analyzing some biological samples for chromium using a standard Cr(VI) solution for external calibration.
Cr standards are typically supplied in a 2% nitric acid matrix. That ...
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