Questions tagged [numerical-analysis]
The numerical-analysis tag has no usage guidance.
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Why isn't residual standard deviation used in FQY analysis?
I've been measuring relative fluorescence quantum yield (hereafter FQY) for a photosensitive pigment. Most analytical articles and standard operating procedures (SOPs) I've read suggest taking the ...
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Should durations of time be considered to determine final significant figures of answer?
In preparation for AP Chemistry this upcoming semester I've been assigned a number of challenge problems. One of them is as following:
Suppose that polluted air has carbon monoxide $(\ce{CO})$ levels ...
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How should you report measurements and uncertainty for a measuring cylinder with 0.5 mL graduations?
I understand that a common convention is to report the uncertainty of an analogue instrument as plus or minus half of the smallest scale division.
By this logic, a measuring cylinder with $\pu{0.5 mL}$...
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Calculating the weight of a chemical within a liquid mixture
I want to know the weight of ethylene glycol in a mixture of Shellzone 50/50 Antifreeze. I have taken the mid-range of 40-60% from the safety data sheet(SDS) for the amount of ethylene glycol in the ...
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How to (numerically) model a phosphoric acid titration curve
I've been learning how to simulate a 1M phosphoric acid titration curve using numerical methods in R.
So far has this has been the best curve:
Notice how it flattens out (artificially) towards the ...
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The algebraic problem in the equilibrium of weak acids and bases
I have had some trouble verifying the systematic treatment in a weak acid base weak balance. The great equation I must arrive at is this:
and I just can't see clearly how to get that equation from ...
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% coefficient of variation (%CV) for log-linear and log-log regression (calibrations)
I have a data set comprising the peak areas of an analyte measured in spiked calibration samples at 'known' and different concentrations levels. For each concentration level I have 5 replicates. My ...
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How to read a chromatography calibration curve?
I am a high school student who has been studying a bit of chromatography. I came across calibration curve during class and I trying to figure how to read it and use it? I have no clue how to read off ...
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Modelling pH as function of time and position
I already posted this on the Engineering Stack Exchange under Chemical Engineering as I don't know where it's a better fit.
I have a system whose initial state consists of three different sections ...
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Data analysis in TCSPC for fluorescene decay (reconvolution with measured IRF)
I am trying to understand the data analysis of fluorescence decay counts measured by TCSPC technique, particularly with reconvolution with measured IRF.
I am able to get the fitted counts (given by ...
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Column Dispersive Mass Balance analytical / numerical solution
Is there any analytical solution for the most common expression of column mass balance:
$\dfrac{\partial C}{\partial t} + \left(\dfrac{1+\varepsilon}{\varepsilon}\right)\dfrac{\partial q} {\partial t} ...
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Calculating the total uncertainty of the final product
I have performed a large number of calculations in order to determine the ethanol content of wine. These included titrations using burettes, mass measurements using analytical balances, and others. I ...
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accurate measurement from inaccurate tools [closed]
It is a very general question. Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means? For example, average 10 measurements can ...
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Balancing chemical reactions, issues of Gauss's elimination method [duplicate]
I am trying to balance some chemical reactions by using the Gauss' elimination method and I noticed that this method does not work if the creation of a matrix with exactly one degree of freedom is not ...
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Factorizing Slater determinant into product of spin-up and spin-down slater determinant
I am reading the book on MONTE CARLO METHODS IN AB INITIO QUANTUM CHEMISTRY by Hammond and Lester. (Chapter 5-Variational Trial Functions, Section 5.3-Hartree Fock and Beyond, Sub-Section 5.3.3 ...
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