chemistry

Thiosulfoxide

Thiosulfoxide is a chemistry topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Thiosulfoxide rather than just read about it. In short: A thiosulfoxide or thiothionyl compound is a chemical compound containing a sulfur to sulfur double bond, with the formula (R−)(R'−)S=S, where R and R' represent any group (typically fluorine, chlorine, alkoxy, alkyl, aryl or other organyl residues. The thiosulfoxide has a molecular shape known as trigonal pyramidal.

Key takeaways

Thiosulfoxide belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Thiosulfoxide to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Thiosulfoxide from memory before moving on to harder problems.

Reference excerpt

A thiosulfoxide or thiothionyl compound is a chemical compound containing a sulfur to sulfur double bond, with the formula (R−)(R'−)S=S, where R and R' represent any group (typically fluorine, chlorine, alkoxy, alkyl, aryl or other organyl residues. The thiosulfoxide has a molecular shape known as trigonal pyramidal. Its coordination is also trigonal pyramidal. The point group of the thiosulfoxide is Cs. A 1982 review concluded that there was as yet no definitive evidence for the existence of stable thiosulfoxides which can be attributed to the double bond rule which states that elements of period 3 and beyond do not form multiple bonds. The related sulfoxides of the type (R−)(R'−)S=O are very common. Many compounds containing a sulfur-sulfur double bond have been reported in the past although only a few verified classes of actually stable compounds exist, closely related to thiosulfoxides.

Sulfur-sulfur double bonds can be stabilized with electron-withdrawing groups in so-called thionosulfites of the type (R−O−)(R'−O−)S=S. These compounds can be prepared by reaction of diols with disulfur dichloride. Sulfur halides such as disulfur dichloride, Cl−S−S−Cl, can convert to the branched isomer thiothionyl chloride, Cl2S=S; disulfur difluoride exists as an equilibrium mixture with thiothionyl fluoride, F2S=S, which is thermodynamically more stable. These disulfide isomerizations are occasionally studied in silico. N-(Thiosulfinyl)amines of the type R−N=S=S are another group of stable compounds containing a S=S bond. The first such compound was prepared in 1974 reaction of the nitroso compound N,N-dimethyl-p-nitrosoaniline with tetraphosphorus decasulfide. Heating to 200 °C extrudes sulfur in this compound and forms the corresponding azo compound. Disulfur monoxide S=S=O is stable at 20 °C for several days. Occasionally thiosulfates are depicted as having a S=S unit but the sulfur-sulfur bond in it is in fact a single bond.

References

Illustrations

Worked examples

Example 1 — a first encounter with Thiosulfoxide

Start with the simplest possible case. Write down what Thiosulfoxide claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Thiosulfoxide before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Thiosulfoxide ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Thiosulfoxide

In research: Thiosulfoxide appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Thiosulfoxide in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Thiosulfoxide is common in secondary-school and first-year university syllabi. It links to neighbouring topics Sulfur compounds, so understanding it makes those chapters shorter.
In everyday life: Look for Thiosulfoxide outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Thiosulfoxide in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Thiosulfoxide means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Thiosulfoxide out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Thiosulfoxide in simple terms?

Why does Thiosulfoxide matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Thiosulfoxide?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Thiosulfoxide.