Meaning & use
carbon monoxide
Last updated
Meanings
noununcountablechemistry
A poisonous gas with no color or smell, made when fuels such as gas, oil, wood or petrol burn without enough air.
Grammar: A mass noun used without an article: carbon monoxide is dangerous.
Patterns
- carbon monoxide poisoning
- a carbon monoxide detector
A faulty heater can leak carbon monoxide into a room.
Carbon monoxide is hard to notice because it has no smell.
Firefighters checked the house for carbon monoxide before letting the family in.
noununcountablechemistry
A compound of one carbon atom and one oxygen atom, with the formula CO, studied in chemistry and used in industry.
Grammar: Used as the name of a substance.
Patterns
- produce carbon monoxide
Cars with no filter once produced large amounts of carbon monoxide.
In the lab, students learned how carbon monoxide differs from carbon dioxide.
Steel makers use carbon monoxide to pull oxygen out of iron ore.
Common combinations
- carbon monoxide poisoning
- Dizziness and headaches can be signs of carbon monoxide poisoning.
- carbon monoxide detector
- We put a carbon monoxide detector near the bedrooms.
- carbon monoxide alarm
- The carbon monoxide alarm woke the whole family.
- emit carbon monoxide
- Poorly tuned engines emit carbon monoxide.
- high levels of carbon monoxide
- The test found high levels of carbon monoxide in the garage.
Synonyms and how they differ
- CO
- CO is the chemical symbol and shorthand, used in manuals and warnings, while carbon monoxide is the full name used in everyday speech.
- exhaust fumes
- Exhaust fumes are the mixed gases from engines, and carbon monoxide is only one of the harmful substances in them.
Word family
- carbon noun
- a chemical element found in all living things
- monoxide noun
- an oxide with one oxygen atom
- carbon dioxide noun
- a related gas with two oxygen atoms, breathed out by animals
Commonly confused: carbon monoxide or carbon dioxide?
carbon monoxide vs carbon dioxide
Carbon dioxide (CO2) is the gas we breathe out and plants use, while carbon monoxide (CO) is the much more poisonous gas from incomplete burning.
Practice
Why is carbon monoxide especially dangerous in homes?
Choose one answer.
Carbon monoxide is colorless and odorless, so people may not notice it until they are poisoned. The first option is wrong because the gas has no smell at all.
Make it your own
Write a sentence using “carbon monoxide”, then check it and compare it with the examples above.