chemistry

Potassium ethyl xanthate

Potassium ethyl xanthate 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 Potassium ethyl xanthate rather than just read about it. In short: Potassium ethyl xanthate (KEX, or PEX) is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores.

Key takeaways

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

Reference excerpt

Potassium ethyl xanthate (KEX, or PEX) is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores. It is a potassium salt of ethyl xanthic acid. Many xanthates are known.

Production and properties Xanthate salts are prepared by the action of alkoxides on carbon disulfide. The alkoxide is often generated in situ from potassium hydroxide:

CH3CH2OH + CS2 + KOH → CH3CH2OCS2K + H2O The salt KS2COC5H11, prepared from potassium pentanolate and carbon disulfide, has been characterized by X-ray crystallography. The COCS2 portion of the anion is planar. The C-S bond lengths are both 1.65 Å, and the C-O distance is 1.38 Å. Potassium ethyl xanthate is a pale yellow powder that is stable at high pH, but rapidly hydrolyses below pH = 9:

CH3CH2OCS2K + H+ → CH3CH2OH + CS2 + K+ Oxidation of xanthate salts gives diethyl dixanthogen disulfide:

4 CH3CH2OCS2K + 2 H2O + O2 → 2 (CH3CH2OCS2)2 + 4 KOH KEX is a source of ethylxanthate coordination complexes. For example, the octahedral complexes (CH3CH2OCS2)3Cr, (CH3CH2OCS2)3In, and (CH3CH2OCS2)3Co have been prepared from KEX.

Applications Potassium ethyl xanthate is used in the mining industry as a flotation agent for the extraction of the ores of copper, nickel, and silver. The method exploits the affinity of these "soft" metals for the organosulfur ligand. Potassium ethyl xanthate is a useful reagent for preparing xanthate esters from alkyl and aryl halides. The resulting xanthate esters are useful intermediates in organic synthesis.

Safety The LD50 is 103 mg/kg (oral, rats) for potassium ethyl xanthate.

References

Illustrations

Worked examples

Example 1 — a first encounter with Potassium ethyl xanthate

Start with the simplest possible case. Write down what Potassium ethyl xanthate 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 Potassium ethyl xanthate 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 Potassium ethyl xanthate 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 Potassium ethyl xanthate

In research: Potassium ethyl xanthate 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 Potassium ethyl xanthate 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: Potassium ethyl xanthate is common in secondary-school and first-year university syllabi. It links to neighbouring topics Metallurgical processes, Potassium compounds, Thiocarbonyl compounds, so understanding it makes those chapters shorter.
In everyday life: Look for Potassium ethyl xanthate 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 Potassium ethyl xanthate in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Potassium ethyl xanthate 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 Potassium ethyl xanthate out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Potassium ethyl xanthate in simple terms?

Potassium ethyl xanthate (KEX, or PEX) is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores.

Why does Potassium ethyl xanthate 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 Potassium ethyl xanthate?

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 Potassium ethyl xanthate.