A Reactor Is Where a Reaction Is Kept Under Control
A reactor is a vessel where a chemical or nuclear reaction takes place. The point of one is control rather than power.
A reactor is a vessel or installation designed to hold a reaction and keep it steady. That is the whole engineering problem: a nuclear reactor produces the same reaction as a weapon, but arranged so that it proceeds slowly and can be shut down. Control rods absorb neutrons and slow the chain reaction on demand.
- A nuclear power installation. *A pressurised water reactor.*
- A vessel for chemical reactions. *A batch reactor.*
- Reactor as a modifier. *Reactor core.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | reactor | A small reactor. |
| Plural | reactors | Two reactors. |
| Verb | react | React with acid. |
| Noun | reaction | A chain reaction. |
| Adjective | reactive | A reactive metal. |
How it is used in a sentence
- The reactor was taken offline for maintenance.Power generation.
- Control rods absorb neutrons.Slowing the chain reaction.
- The mixture is heated in a sealed reactor.Chemistry.
Reactor vocabulary
- Core — where the fuel sits
- Moderator — slows neutrons so the reaction continues
- Control rods — absorb neutrons to slow or stop it
- Coolant — carries heat away, often water
- Criticality — the state where the reaction sustains itself
From *react*, from Latin *re-*, back, and *agere*, to do or drive. The nuclear sense dates from the 1940s; the chemical sense is older.
Can a power reactor explode like a bomb?
No. The fuel is not enriched enough and the geometry is wrong. Serious accidents involve steam, hydrogen or overheating rather than a nuclear explosion.
What does *going critical* mean?
That the chain reaction is exactly self-sustaining. It is the normal operating state, not a warning.