permanent hardness: meaning, definition, pronunciation and examples
C1Technical/Specialized
Quick answer
What does “permanent hardness” mean?
Water hardness (mineral content) that cannot be removed by boiling, primarily caused by calcium and magnesium sulfates and chlorides.
Audio
Pronunciation
Definition
Meaning and Definition
Water hardness (mineral content) that cannot be removed by boiling, primarily caused by calcium and magnesium sulfates and chlorides.
In technical contexts, it refers to the level of dissolved minerals in water that cannot be precipitated by heating, requiring chemical treatment for removal. In metaphorical or business use, it can describe an ingrained, difficult-to-alter condition or standard.
Dialectal Variation
British vs American Usage
Differences
No significant difference in technical definition. 'Hardness' in a water context is standard in both. However, in everyday discussion about water, regional terms for 'hard water' might be more common.
Connotations
Identical technical connotation. In non-technical metaphorical use (rare), the British might be slightly more likely to use it due to historical prevalence of hard water areas and domestic water softeners.
Frequency
Extremely low frequency in general discourse in both regions, limited to chemistry, plumbing, environmental science, and manufacturing texts.
Grammar
How to Use “permanent hardness” in a Sentence
The permanent hardness (of the water) is high.To remove permanent hardness, you need...Permanent hardness is caused by...They measured the permanent hardness.We have a problem with permanent hardness.Vocabulary
Collocations
Examples
Examples of “permanent hardness” in a Sentence
verb
British English
- (No direct verb form. Usage would be periphrastic: 'The water softener is designed to *remove* permanent hardness.')
- (No direct verb form. 'The process *reduces* the permanent hardness.')
American English
- (No direct verb form. 'They need to *treat* the water for permanent hardness.')
- (No direct verb form. 'The system *eliminates* permanent hardness.')
adverb
British English
- (No direct adverb form. Use adverbial phrase: 'The water is *permanently hard* due to sulfates.')
- (No direct adverb form.)
American English
- (No direct adverb form. 'The minerals are *permanently bound* in solution, causing hardness.')
- (No direct adverb form.)
adjective
British English
- The lab report highlighted the *permanent-hardness* concentration.
- We need a *permanent-hardness* removal unit.
American English
- The test results show a *permanent-hardness* problem.
- A *permanent-hardness* ion exchange system was installed.
Usage
Meaning in Context
Business
Rare. Might appear in reports for companies selling water softeners, in industrial facility management (e.g., 'The permanent hardness level in the coolant loop requires treatment to prevent scaling.')
Academic
Common in chemistry, environmental science, geology, and engineering textbooks and papers on water quality.
Everyday
Very rare. Only used by informed individuals discussing home water treatment systems.
Technical
Primary domain. Used in water analysis, boiler operation, manufacturing processes, plumbing, and chemical engineering.
Vocabulary
Synonyms of “permanent hardness”
Strong
Neutral
Weak
Vocabulary
Antonyms of “permanent hardness”
Watch out
Common Mistakes When Using “permanent hardness”
- Using 'permanent hardness' to describe a tough object or person (incorrect).
- Confusing it with 'temporary hardness'.
- Pronouncing it as three separate words without linking the compound noun: /ˈpɜː.mə.nənt/ /ˈhɑːd.nəs/ instead of /ˈpɜː.mə.nənt ˈhɑːd.nəs/.
- Misspelling as 'permanant hardness'.
- Using it without the technical context of water or solutions.
FAQ
Frequently Asked Questions
Temporary hardness is caused by calcium and magnesium bicarbonates and can be removed by boiling, which precipitates them as carbonate scale. Permanent hardness is caused by calcium and magnesium sulfates, chlorides, and nitrates; it remains in solution after boiling and requires chemical treatment for removal.
Not directly. The minerals that cause hardness (calcium and magnesium) are not harmful and can be beneficial. However, permanent hardness can cause scale buildup in pipes and appliances, reducing efficiency and increasing costs. It can also interfere with soap lathering.
It is measured indirectly. Total hardness and temporary hardness (by boiling and titrating) are determined separately. Permanent hardness is calculated as: Permanent Hardness = Total Hardness – Temporary Hardness. Units are typically parts per million (ppm) or milligrams per litre (mg/L) of calcium carbonate equivalent.
Yes, standard ion-exchange water softeners are specifically designed to remove the calcium and magnesium ions that cause both temporary and permanent hardness, replacing them with sodium or potassium ions.
Water hardness (mineral content) that cannot be removed by boiling, primarily caused by calcium and magnesium sulfates and chlorides.
Permanent hardness is usually technical/specialized in register.
Permanent hardness: in British English it is pronounced /ˈpɜː.mə.nənt ˈhɑːd.nəs/, and in American English it is pronounced /ˈpɝː.mə.nənt ˈhɑːrd.nəs/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “(none specific to this technical term)”
Learning
Memory Aids
Mnemonic
Imagine a PERMANENT marker stain on fabric (hard to remove). Permanent hardness is like minerals that make a PERMANENT mark in water, not washed out by boiling. Temporary hardness is like pencil, removable (by boiling).
Conceptual Metaphor
HARDNESS as PERSISTENCE/RESISTANCE (to change/removal).
Practice
Quiz
What primarily causes permanent hardness in water?