Questions tagged [numerical-analysis]
The numerical-analysis tag has no usage guidance.
31
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How do I round a calculation involving both addition/subtraction and multiplication/division to the correct number of significant figures?
I'm just learning about significant figures (sig figs) in my chemistry class, and I'm confused about the rules. An example to my problem: if I had the following expression:
$$\left ( \frac{2.378 - 1.2}...
- 243
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2
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How to (numerically) model a phosphoric acid titration curve
I've been learning how to simulate a 1M phosphoric acid titration curve using numerical methods in R.
So far has this has been the best curve:
Notice how it flattens out (artificially) towards the ...
- 133
6
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2
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Factorizing Slater determinant into product of spin-up and spin-down slater determinant
I am reading the book on MONTE CARLO METHODS IN AB INITIO QUANTUM CHEMISTRY by Hammond and Lester. (Chapter 5-Variational Trial Functions, Section 5.3-Hartree Fock and Beyond, Sub-Section 5.3.3 ...
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accurate measurement from inaccurate tools [closed]
It is a very general question. Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means? For example, average 10 measurements can ...
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1
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Calculate the number of moles produced per hour per liter of air?
A reaction of importance in the formation of smog is that between ozone and nitrogen monoxide described by
$$
\ce{O3(g) + NO(g)->O2(g) + NO2(g)}
$$
the rate law for this reaction is:
$$
\text{...
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4
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1
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574
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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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4
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1
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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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4
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1
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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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3
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4
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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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4
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Does the addition or multiplication rule have precedence deciding the significant figures in 5×5.364? [duplicate]
How many significant figures should be present in the answer of
$5\times 5.364$?
Addition rule: The result cannot have more digits to the right of the decimal point than either of the original ...
user23923
3
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1
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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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1
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How to numerically solve a reaction network with fast equilibrium steps?
For example If I have to solve the following reaction numerically
\begin{align}
*\ce{ + A(g) &<=>[K1] [A*]} \tag{1}\\
\ce{[A{*}] &<=>[k1][k-1] [B{*}]} \tag{2}\\
\ce{[B*] &&...
- 146
3
votes
0
answers
341
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Good software/module in python to determine nuclear attraction integral in Slater type orbital basis sets
I am trying to solve a Hamiltonian of one electron and 10 stationary nuclear centers. here, the electron is treated quantum mechanically and nuclear centers are treated classically objects. The ...
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0
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Limit to volume change in a discretized mathematical model?
I have set up a mathematical model describing the diffusion of ozone out of a gas bubble. The bubble is surrounded by a thin gas film. So actually, the model describes the diffusion of ozone through ...
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1
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what is the issue in evaluating two electron integral?
What sort of issue is there in two electron integral in quantum chemistry ? Is it a problem of convergence when we do numerically? Can someone suggest any review article or reference articles which ...
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