# Tag Info

### How to find out pH of aquarium and apply it when adding HCl?

You are seriously over-thinking it. Get some liquid indicator ( methyl blue ?). Measure the pH. Likely no correction will be needed. Natural waters generally have buffering. When I was a boy in ...
• 3,541

### What's the pH of a solution knowing only pKa, mass and volume? (no molecular mass known)

Unfortunately knowing only the pKa, the mass of the acid in the solution and the volume of the entire aqueous mixture it's not enough, one will always end up with an equation with two variables, which ...

### How to find out pH of aquarium and apply it when adding HCl?

If you need to check the pH of your aquarium, you can use pH test paper. Its results can be seen immediately, which is convenient for you to carry out the next step. Sincerely recommend this pH test ...

### What determines strength of nucleophile--Polarisability or Electron density

Nucleophilicity is a kinetic concept, and differs from basicity which is a thermodynamic concept. There are some molecules which are both strong bases, like the ethoxide anion, and hence some factors, ...
• 93
1 vote

### Could neutralisation of safe chemicals produce dangerous ones?

If you're using oxidizing acids (mainly nitric, perchloric, chloric, perbromic, bromic, periodic, iodic, also potentially selenic and arsenic acids and obviously chromic or permanganic acids and ...

### What determines strength of nucleophile--Polarisability or Electron density

The most correct answer would be that the bromide ion is both a strong nucleophile (since the electrophiles in reactions involving bromide are usually soft) and both a weak base in aqueous solution(...
• 677

### Which one is more Bronsted basic?

Yours thoughts seem to be correct. Imidazole pKa is 14.5 and 6.8. Pyrrole pKa is 16.5. You do have a resonance form for the imidazole ring. Additionally, nitrogen is electron withdrawing. The ...

• 34.6k
1 vote
Accepted

### Why is phosphine more acidic than ethylene?

Phosphorus, a third-period element, forms a weaker bond to hydrogen than carbon; see for instance https://chem.libretexts.org/Courses/Valley_City_State_University/Chem_121/Chapter_8%...
• 45.3k
Accepted

### Why do stable covalent compounds react with water

What you meant by "stable" is relative. It is not some absolute. First we need to define "stability". From what you wrote, I assume by "stable" you mean compounds that ...
• 90
Accepted

### Is ethylene more acidic than phosphine?

It seems to be extraordinarily difficult to find a figure for the pKa of a phosphine proton (P-H). However the preparation of alkylsilylphosphines has been reported by nBuLi deprotonation of phosphine ...
• 20k

### Why can't the product of an acid reacting with water react with water itself and produce OH-?

I really like this question because it digs at wanting to understand what's going on beneath the equations you've been given to know why that equation works. Orthocresl answered it really well, but I ...
• 21
Accepted

### Why can't the product of an acid reacting with water react with water itself and produce OH-?

It definitely does. Let's simplify it to a monoprotic acid (like acetic acid, $\ce{CH3COOH}$), which I'll just represent as $\ce{HA}$ for simplicity. In a solution of the acid, you will have all of ...
• 68.7k
Accepted

• 34.6k