barium chromate
Very Low / SpecializedTechnical / Scientific
Definition
Meaning
An inorganic chemical compound with the formula BaCrO4, appearing as a yellow crystalline powder, insoluble in water.
Used industrially as a pigment (e.g., lemon yellow, ultramarine yellow) and in corrosion-resistant coatings for metals; also encountered in laboratory contexts and some historical pyrotechnic compositions.
Linguistics
Semantic Notes
The term exclusively refers to the chemical compound; it is not used metaphorically. It is a count noun ('precipitate the barium chromate') but can be treated as a mass noun in contexts like 'adding barium chromate'.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences. Spelling of related terms follows regional norms (e.g., 'colourant' vs. 'colorant').
Connotations
No specific regional connotations; purely technical term.
Frequency
Equally rare and specialized in both dialects, confined to chemical, industrial, and conservation fields.
Vocabulary
Collocations
Grammar
Valency Patterns
[Verb] + barium chromate + [Prepositional Phrase] (e.g., 'Filter the barium chromate from the solution.')Barium chromate + [Verb] + [Adverbial] (e.g., 'Barium chromate settles slowly.')Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “None”
Usage
Context Usage
Business
Rare; potentially in supply chain discussions for pigments or specialty chemicals.
Academic
Primary context: in chemistry, materials science, and art conservation journals and textbooks.
Everyday
Virtually never used.
Technical
Standard term in chemistry labs (analytical, inorganic), industrial paint/pigment formulation, and corrosion engineering.
Examples
By Part of Speech
verb
British English
- The barium chromate was filtered and washed.
- They chromated the surface using a barium salt.
American English
- We precipitated the barium chromate for analysis.
- The process chromates the barium in situ.
adverb
British English
- The powder precipitated chromate-yellow.
- The solution reacted chromate-specifically.
American English
- The coating was applied chromate-rich.
- It tested positive chromate-quick.
adjective
British English
- The barium-chromate coating proved effective.
- A barium chromate test was performed.
American English
- The barium-chromate pigment is stable.
- We need a barium chromate standard.
Examples
By CEFR Level
- This yellow powder is called barium chromate. (In a very simple science video.)
- The chemist showed us a jar of bright yellow barium chromate.
- Due to its low solubility, barium chromate is used as a corrosion inhibitor in primers.
- The analytical procedure hinges on the selective precipitation of barium chromate from a buffered medium, thereby eliminating interfering cations.
Learning
Memory Aids
Mnemonic
Think 'Ba' (chemical symbol for barium) makes a 'yellow crown' (from 'chroma' meaning colour) – a yellow crown of barium.
Conceptual Metaphor
Not applicable; the term is literal and technical.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid literal translation of parts ('бариевый хромат' is correct).
- Do not confuse 'chromate' with 'chromium' or 'chrome'; it specifies a specific anion.
- In Russian, the pigment name 'жёлтый ультрамарин' is a direct equivalent for the historical pigment form.
Common Mistakes
- Mispronunciation: 'chromate' as /ˈkrɒm.eɪt/ (like 'chrome') instead of /ˈkrəʊ.meɪt/ (UK) / ˈkroʊ.meɪt/ (US).
- Misspelling as 'barium chromite' (a different compound).
- Incorrect pluralisation: 'barium chromates' is acceptable when referring to multiple batches or types, but 'barium chromate' often used collectively.
Practice
Quiz
What is the primary industrial use of barium chromate?
FAQ
Frequently Asked Questions
Yes. It is toxic if ingested or inhaled, and contains chromium(VI), which is carcinogenic and a strong oxidiser. It requires careful handling with appropriate personal protective equipment.
Its yellow colour arises from charge-transfer electronic transitions within the chromate ion (CrO4^2-), which absorbs light in the violet/blue region of the spectrum, reflecting yellow.
Historically, yes, in some artists' pigments (e.g., lemon yellow) and anti-corrosion paints. Its use has declined due to toxicity, but it may still be found in some specialty industrial coatings.
It is typically prepared by metathesis: mixing a soluble barium salt (like barium chloride) with a soluble chromate salt (like potassium chromate), resulting in immediate precipitation of yellow barium chromate.