# All Questions

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### How to calculate the formal charge of sulfate ion?

I found a site with this formula if you will, Formal Charge = [Number of valence electrons on atom] – [non-bonded electrons + number of bonds] I don't think I am using it correctly in finding the ...
2k views

### Figuring out the volume of air trapped inside a bottle of water

I am doing a chemistry lab report on figuring out the volume of air trapped inside a bottle. Here is the procedure: Fill a larger container or tub about half full with tap water Fill a 2 L plastic ...
456 views

### Equilibrium constant

I know that equilibrium constant depends on temperature and pressure. But according to Le Chatelier's principle when we change pressure of reagents the equilibrium is the same. Why?
2k views

### Why does molten plastic (PLA) stick to metals (AL)?

I know this is broad so I will narrow: Why does molten PLA stick to Aluminum? I ask because I'm looking for a way to prevent/reduce the friction of the plastic inside the aluminum barrel of a 3D ...
3k views

### Why does the extent of racemisation in an SN1 reaction depend on the solvent used?

Why is it that the extent of racemisation is greater in an $S_N 1$ reaction caried out using a polar protic solvent but the racemisation is not as extensive if an aprotic solvent is used although the ...
2k views

### Is the activation barrier of a reaction related to the free energy or heat of formation of its reactants?

The energy barrier for activation appears in the derivation of a bimolecular reaction through collision or transition state theory, but it seems that from looking at diagram such as this one it seems ...
986 views

### How to transform a tertiary alcohol to a carboxyl?

I am trying to transform a lipid with a tertiary alcohol into a carboxylic acid. More specifically, I want to convert to diplopterol (see below) into something homologous to cholesteryl hemisuccinate ...
1k views

### Time to effervescent an effervescent tablet

Say I have an effervescent tablet and I put in water. I thought that if I break the tablet in two halves it would dissolve quicker than with the whole table (without breaking), but it actually takes ...
855 views

### Bonding and Antibonding

So I understand, electrons exist in orbitals, mainly s, p, d, f and that when they bond with one another it will form sigma and pi bonds and that whether it bonds in a certain orientation a molecular ...
580 views

### Why do aqueous solutions always have to be electrically neutral?

I was reviewing some analytical chemistry and stumbled upon a section that explained the imperfection of using a salt bridge. It said that the using dissimilar ions is a problem because in, for ...
2k views

### Electrolysis: Water to Hydrogen gas?

I recently conducted an experiment where I electrolyzed a solution of sodium chloride. I was using a copper coin as the anode, and I observed a pale blue precipitate in the cup when I was done with ...
168 views

### Are there any free electrons in metal vapor?

Metals contain free moving electrons, in both the solid and liquid state. Does this happen when it is in vapor form?
206 views

### synthesizable functional groups [closed]

I was told in this question: https://chemistry.stackexchange.com/questions/4789/synthesizability-and-energy-minimization-of-a-structure/4791#4791 to [Count the] "number of accessible functional ...
93 views

### How do you determine which entity gains or loses an H+ in an equation?

$$\ce{HCO3- (aq) + H2O(l) <=> H2CO3(aq) +OH- (aq)}$$ I do not understand why this makes an Arrhenius base and why it doesn't form: $$\ce{HCO3- (aq) + H2O(l) <=> CO3^2- (aq) +H3O+ (aq)}$$ ...
2k views

### I have to write a Python program relating with molecular weight. Any insight?

Write a program that determines the molecular weight of a chemical compound based on the number of hydrogen, carbon, and oxygen atoms in the compound. You should use the following atomic weights: \...
1k views

### Approximation of electron density of a small molecule

Starting point for Quantum Theory of Atoms in Molecules (AIM) is the electron density $\rho(r)$. It could be determined experimentally (X-ray diffractions). I want to know how can we estimate them ab ...
1k views