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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Dissolving cast iron in nitric acid
Decades ago my job was to find the silicon content in cast iron gravimetrically. The first step was dissolving the sample in hot Nitric acid. Did this turn all of the constituents in the sample, ...
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Organic molecules with 21.62% oxygen
I have been told to answer the following question:
Seven different compounds, all either alcohols or ethers,
contained 21.62% oxygen. Find the structural formula for all of these compounds and ...
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Does ICP-OES detect molecules in suspension?
I'm curious whether ICP-OES has the ability to detect molecules in suspension?
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Why aren't lasers used as light sources for atomic absorption spectroscopy?
Atomic absorption spectroscopy yields extremely narrow signals. It is difficult to separate white light with sufficient precision using monochromators, and hollow cathode lamps are often used as light ...
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Lactic acid - Elementary analysis
Lactic acid is a hydroxy carboxylic acid that can form in the muscles and lead to soreness. The molecular weight of the lactic acid is $\ce{90.1 g/mol}$. Elemental analysis shows that the substance ...
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Determining the chemical formula of a polyiodide Salt
I've got a compound with formula $\ce{N(CH3)4.I(I2)_x}$. By mass I've got $\pu{0.138 g}$ of $\ce{I2}$ present out of $\pu{0.189 g}$ of polyiodide added. How do I find $x$?
This is the exact part of ...
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How does the electron configuration correlate with the emission spectrum of an ionic compound? [closed]
trying to find a way to correlate the electron configuration of an ionic compound (ie. Cupric sulfate, potassium chloride, Cupric chloride, sodium carbonate, strontium chloride) with its emission ...
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In TOF Mass Spectrometry how does the detector 'know' the difference between ions of different elements?
After the positive ions have been accelerated, I know that they travel through the drift zone at different speeds due to their masses.
But surely, a heavier ion/element that enters the drift zone ...
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Quantitative elemental analysis in mixtures with internal standard normalization
I am trying to make a quantitative model for Laser Induced Breakdown Spectroscopy (LIBS) analyzing metal alloy samples. I am using an internal standard normalization (so far it produced the best ...
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XPS analysis intrepretation
A lab presented me with an elemental composition (mainly metals in char) derived from an XPS analyzer and mentioned that binding energies suggested a list of compounds (various oxides, sulfides and ...
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Oxide and chloride of a metal [closed]
I found this problem:
The oxide of a metal contains 60.0% metal and the chloride of the same metal contains 25.26% metal (in mass percents). What are the possible formulas for the oxide and the ...
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Calculation of empirical formula from elemental analysis
A compound contains 40.0% Carbon, 6.7% Hydrogen, and 53.3% Nitrogen (by mass). Calculate the empirical formula.
I'm getting $\ce{C7H14N8}$, but my professor says it is $\ce{CH2N}$.
Which is the ...
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How to determine DDVP quality before appplication
The question is quite straightforward I need to determine the quality of 2,2-dichlorovinyl dimethyl phosphate (commonly abbreviated as DDVP) it is solved in xylene (50%). The purpose is to know if it ...
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metal oxide analysis
I am looking in to analytical techniques for a future project. I may have a mixture of metals, i.e. an alloy, which I am thinking XRF spectroscopy would be the best quantitative technique. I could ...
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How to test for magnesium and calcium oxide?
Is there a way to test for $\ce{MgO}$ and $\ce{CaO}$?
I want to prove that $\ce{MgO}$ and $\ce{CaO}$ are created from their respective calcinations.
$$\ce{MgCO3 (s)->[heat] MgO(s) + CO2(g)}$$
$$...
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