Top new questions this week:
|
|
I’ve been trying to learn quantum chemistry at an introductionary level. While reading I’ve found out that the Born-Oppenheimer approximation seems to be the reason for the basic and crucial model of …
|
|
I have heard in various situations people use a wet fabric to breathe better in situations where a lot of fire-based smoke is present (like near wildfires). I wanted to know if there was any truth to …
|
|
While trying to understand this paper, I read the following method for calculating the polarizability of different Xe isotopes: Quantum chemical calculation of the exact polarizability of each xenon …
|
|
In college, when deriving the Langmuir isotherm for gas-solid adsorption, the professor proposed a modified version of the Van der Waals state equation, what he called the “pseudo Van der Waals …
|
|
Problem From Hayward’s Quantum Mechanics for Chemists [1, p. 36] 2.3. Calculate the wavelength of light that will be absorbed when a it electron in hexa-1,3,5-triene, $\ce{CH2=CH—CH=CH—CH=CH2},$ is …
|
|
I hope this is the right place to ask. We have this exercise without solution One litre of diluted sodium hydroxide solution (c = 0.15mol/litre) is to be prepared in the laboratory. The titer from …
|
|
Background From the December 29, 2022 NPR article To peer into Earth’s deep time, meet a hardy mineral known as the Time Lord: “(Zircons) are really the best markers of Earth’s time, or the …
|
Greatest hits from previous weeks:
|
|
I have a chemistry test coming up and I might need to know the charge that goes with the different ions like $\ce{SO4}$ has $-2$, $\ce{NO2}$ is $-1$ and $\ce{PO4}$ is $-3$. Is there an easy way to …
|
|
In High School I learned that an exothermic reactions releases energy, while an endothermic reaction needs energy to occur. Now I learned that there is a separate, somewhat similar classification …
|
|
If one considers boiling points (in °C) of primary alcohols, one finds the following: methanol: 65 ethanol: 79 1-propanol: 97 1-butanol: 117 1-pentanol: 138 This trend is due to Van der Waals forces …
|
|
I was working on something in school and came across the question: Why does the temperature not change much during a phase change? I’m really not sure why this happens in matter and I couldn’t …
|
|
How can we theoretically decide the acidic or basic nature of an oxide? What are the reasons/ factors which make an oxide acidic, basic, amphoteric or netural?
|
|
What causes the melting and boiling points of noble gases to rise when the atomic number increases? What role do the valence electrons play in this?
|
|
A mixture is made by combining 110 mL of 0.15 M $\ce{HCl}$ and 215 mL of 0.055 M $\ce{HI}$. What is the pH of the solution? $$\ce{HCl -> H+ + Cl-}$$ $$\ce{HI -> H+ + I-}$$ According to what I …
|
Can you answer these questions?
|
|
My understanding is that hydrogen bonds formed by proteins require the NH2 / COOH to be neutral. Hence to find out when the hydrogen bonds are the strongest will depend on the absolute charge of the …
|
|
I was curious about the highest known Tc for type 1 superconductors. This list suggests lead near 7K is as good as it gets for type-1 superconductors but I wonder if that is true given the current …
|
|
I am studying the effect that pH has on solubility of metal salts. One example I came across is the idea that the solubility of $\ce{PbI2}$ is not strongly affected by the addition of strong acid to …
|
