# Why does an mercury ore exist as HgS?

Chemistry Asked on January 2, 2022

Cinnabar($$ce{HgS}$$) is one of the most common ores of mercury.

Why does it not exist at $$ce{HgO}$$ or some other such compound?

Is there any reason for why it is so prevalent?

Does it react less with other compounds, or maybe due to some solid structure of HgS having some characteristic property giving it more stability?

I’m seeking an explanation without the mention of free energy, because it doesn’t properly explain the phenomenon for me. I understand that cinnabar is abundant in the crust, and my question is why is $$ce{HgS}$$ so common?

I am afraid that no one knows why! The superficial rationalizations such as HSAB and ionic size etc are good for decorating general chemistry textbooks.

As scientists, we should accept the fact that all questions which a human mind can generate do not have answers. Unfortunately, as science students, we are trained that every question must have an answer at the back of the book.

There is a whole field of geology, called ore genesis which tries to think of the origin of minerals and ores Ore Genesis on Wikipedia. It is a remarkable wonder and miracle of Nature, as how it deposits ore in certain chemical forms.

More specifically, you would search the geochemistry literature, you would see how complex is the whole concept e.g. if you go through Quicksilver Deposits of Chile Quicksilver deposits you can get a feel.

Answered by M. Farooq on January 2, 2022

Why $$ce{HgS}$$ and not $$ce{HgO}$$?

Because of HSAB. F'x has already answered a previous question of why mercury has propensity towards thiols(or in general sulfur). Quoting the relevant information:

In Pearson's HSAB theory (hard and soft acids and bases), the reason the $$ce{S-Hg}$$ bond is be stronger than the $$ce{O-Hg}$$ can be explained because $$ce{S^2-}$$ is a soft basis and $$ce{Hg(II)}$$ is a soft acid, making a good fit while $$ce{O^2-}$$ is harder.

Answered by Nilay Ghosh on January 2, 2022

## Related Questions

### How can I properly calculate the isoelectric point (pI) of amino acids?

1  Asked on October 5, 2021 by rahul-verma

### How do I prepare 2-(3-azido-3-oxopropoxy)ethyl methacrylate from methacrylic acid?

1  Asked on October 5, 2021 by jonathan-g

### Disproportionation of silver(I) in aqueous solution

2  Asked on October 5, 2021 by isabel

### What is “protein redox conformation”?

0  Asked on October 5, 2021 by cowperkettle

### Why are antibonding molecular orbitals formed?

1  Asked on October 5, 2021 by ordinary-chemistry-student

### Reaction of amines with diethyl oxalate (Hofmann amine separation method)

2  Asked on October 5, 2021 by ritwik-das

### Numerical related to crystallisation of water below its freezing point

5  Asked on October 5, 2021 by gaurang-tandon

### Does acrolein give Fehling’s test?

3  Asked on October 5, 2021 by joshishere

### Is any symmetry element conserved during a supra-antarafacial cyclo addition of two cis-butadiene units

0  Asked on October 5, 2021 by hans-wurst

### Why is Thorium (At. no. 90) an f-block element at all?

1  Asked on October 5, 2021 by user82401

### Reactivity of different alcohols with NaNH2 and CH3I

1  Asked on October 5, 2021

### Ortho-para directing and meta directing groups: Activating or deactivating the aromatic ring?

1  Asked on October 5, 2021

### Why HBr has stronger attraction between molecules than CH3NH2?

1  Asked on October 5, 2021 by molly_k

### How does C−Br bond obtain energy through solvation?

0  Asked on October 5, 2021 by ramathuzen

### Conductometric titrations: dilution effect

1  Asked on October 5, 2021

### Steric effect of t-butyl group on SN1 on a cyclohexane ring

1  Asked on October 5, 2021 by safdar-faisal

### Calculation of pH in acid base reaction

2  Asked on October 5, 2021 by its-probable

### Role of intermediate in determining the exothermic or endothermic nature of reaction

2  Asked on October 5, 2021 by shreyansh