Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [chemistry]

Questions related to mathematical chemistry which include application of mathematics to problems in chemistry and the development of mathematical methods suitable for such applications and for the formulation of chemical theories

224 questions
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Building a tetrahedron from two defined vectors?

I am currently writing a program that computes specific molecular bond angles for one of my research projects but am running into some trouble. Suppose I want a tetrahedron with vertices A, B, C, D. I know three ${x,y,z}$ coordinates: one coordinate…
James
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3 answers

Significant Figures in quantity?

I am still having trouble grasping significant figures. How many significant figures would be in this quantity? $01010.0$ I feel like it is 3, but not quite sure.
user266519
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1 answer

Does this averaging function have a name? ("sigma profiles" in chemistry)

I am looking for a mathematical (!!) answer, NOT a chemical one, hence the post to Mathematics. Quick description: Solvation modelling with for example COSMO-SAC uses something called a sigma profile calculated over a cavity (volume). We have…
DetlevCM
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Is it possible to balance a chemical equation without using trial and error?

Possible Duplicate: Balance chemical equations without trial and error? Thanks Ben, the other answer was helpful... but is it possible to do it when, say, five variables are involved? E.g.: $\textrm{Na}_2\textrm{CO}_3 + \textrm{HCl} \to…
David Rodriguez
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How to calculate n-percent solution given impure chemical?

I couldn't find a Stack Exchange site for computational chemistry, so hope this is apropos for this forum. I can get $80\%$ pure sodium chlorite and I want to make a $28\%$ solution of it. Though I'm getting some conflicting information on the web,…
jcomeau_ictx
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Chemistry: Gravimetric determination of copper in ore

Hey, sorry for the non so mathematical question but that's the only place where I'd thought someone would answer this so here we go. I'm doing a chemistry homework and I have to answer this very question: If 50 grams of a particular mineral…
Tommy B.
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Calculate terminal half life and build up

Trying to solve this from a different approach now. started out here Calculate half life of esters Is there a way to find a function that fits the graph below? There are a few criterions. The area of the graph must be A The peak of the graph must…
Roger Johansson
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How were these total contained resources calculated?

I'm an investor trying to understand the technical document of a mining resource. If a mining report listed its indicated resources as: 25.59 Mt (meaning Million Tons) 1711 ppm How is the contained resource in lbs determined? The resource is…
pstatix
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Modelling an energy profile with/without catalyst

I'm trying to make a data table that can be plot to model the energy profile of a chemical reaction with/without catalyst. example image This is essentially what I want to plot, and I'm at a loss for how to simply make 2 curves like that,…
Sam Thornton
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1 answer

What does the $-1$ mean in $2\mu g/L^{-1}$

What does the $-1$ mean in the expression $2\mu g/L^{-1}$? Does it literally mean multiply by $-1$?
C_B
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The Coffin-Manson is an extension of the Arrhenius equation

Given the following problem: Each TV goes through 10,000 on/off cycles in its field life. The temperature change from these on/off cycles is from 20°C to 60°C. We can perform thermal cycle testing of the PCB in the TV from 0°C to 100°C without…
Martinho Luterinho
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Calculate half life of esters

edit - wrong part of stack exchange
r0cc0
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1 answer

Amount of NaHCO3 needed to neutralize HCl

With the equation: HCl + NaHCO3 --> NaCl + CO2 + H2O Find the number of grams of NaHCO3, to three significant figures, required to neutralize 75 mililitres of 0.110 mol/l HCl. I'm stuck on this problem. I think I either use the molarity formula…
Grimestock
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Determining Mass of Lithium

What is the mass of 1.3 x 10^(23) atoms of lithium. Lithium has a mass of 6.94, so I assumed that it'd be 6.94 x 1.3 x 10^(23), but that wasn't the case. I wasn't given much practice and I'm not sure how to proceed. Any advice in the right direction…
Grimestock
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Uncertainty powers

In class, we are working with powers of uncertainties. The teacher, however, handed me an extremely technical article, and it makes very little sense. Could one please explain to me step by step how to solve this…
user266519
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