nitrohydrochloric acid
C1/C2Scientific, Technical
Definition
Meaning
A highly corrosive, fuming yellow liquid mixture of concentrated nitric acid and concentrated hydrochloric acid, typically in a 1:3 ratio.
The mixture, also known as aqua regia, capable of dissolving noble metals such as gold and platinum. Its historical and technical significance extends to metallurgy, chemistry, and analytical procedures.
Linguistics
Semantic Notes
The term is a compound noun naming a specific chemical mixture. In technical contexts, 'aqua regia' is a more common synonym. It is not typically referred to outside chemistry or metallurgy.
Dialectal Variation
British vs American Usage
Differences
No significant differences in term usage. Spelling follows standard national conventions for 'acid' (no difference).
Connotations
Identical in both dialects—purely technical/scientific with connotations of danger, power, and chemical reactivity.
Frequency
Extremely low frequency in general discourse. Usage is confined to identical scientific/technical fields in both regions.
Vocabulary
Collocations
Grammar
Valency Patterns
[substance] + is dissolved/digested in + nitrohydrochloric acidto prepare + nitrohydrochloric acidto add + nitrohydrochloric acid + to + [material]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “N/A”
Usage
Context Usage
Business
Rare; potentially in contexts of precious metal refining or chemical supply.
Academic
Used in chemistry, metallurgy, materials science, and analytical chemistry papers and textbooks.
Everyday
Virtually never used. Would be replaced by general terms like 'powerful acid' or 'chemical mix'.
Technical
Primary context. Used in laboratory manuals, safety protocols, and procedures for digesting metals or cleaning glassware.
Examples
By Part of Speech
verb
British English
- The sample was nitrohydrochloric-acid-digested overnight.
- They nitrohydrochloric-acid-treated the crucible.
American English
- The alloy was nitrohydrochloric-acid-digested for analysis.
- We nitrohydrochloric-acid-cleaned the apparatus.
adjective
British English
- The nitrohydrochloric acid solution must be fresh.
- Use proper nitrohydrochloric acid precautions.
American English
- Follow the nitrohydrochloric acid procedure carefully.
- A nitrohydrochloric acid fume hood is required.
Examples
By CEFR Level
- Nitrohydrochloric acid is a dangerous chemical. (Context: basic hazard warning)
- In the lab, we learned that nitrohydrochloric acid can dissolve gold.
- The geologist used nitrohydrochloric acid to digest the rock sample and analyse its gold content.
- Aqua regia, or nitrohydrochloric acid, is instrumental in ICP-MS sample preparation due to its ability to form soluble chloro complexes with platinum-group metals.
Learning
Memory Aids
Mnemonic
Think: NITROgen + HYDROchloric = NITROHYDROCHLORIC. It's the 'royal' (regia) acid that attacks the 'king' of metals (gold).
Conceptual Metaphor
A 'king-maker' or 'king-breaker' substance; something uniquely powerful that can overcome otherwise invulnerable things (like gold).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Прямой перевод "азотно-соляная кислота" является корректным, но более распространенным и узнаваемым термином является "царская водка" (aqua regia). Не переводите дословно как "нитро-гидрохлорическая", так как это калька.
Common Mistakes
- Misspelling as 'nitro-hydrochloric acid' (hyphen often omitted in standard usage).
- Confusing it with nitric acid alone.
- Incorrect pronunciation stress (e.g., on 'chloric' instead of 'chloric').
Practice
Quiz
What is the primary use of nitrohydrochloric acid?
FAQ
Frequently Asked Questions
Yes, nitrohydrochloric acid is the systematic name for the mixture commonly known as aqua regia ('royal water').
It combines the oxidizing power of nitric acid with the complexing ability of chloride ions from hydrochloric acid, forming soluble gold chloride complexes.
No. It is extremely corrosive, releases toxic fumes (chlorine, nitrosyl chloride), and must only be handled by trained personnel using appropriate safety equipment in a fume hood.
It is traditionally prepared by mixing one part concentrated nitric acid with three parts concentrated hydrochloric acid, by volume.