Is it correct to express a scientific fact as a condition?
When water is heated to one hundred degrees Celsius, it starts to boil.
Surely one ought to use the simple present tense because this tense best expresses something that always happens?
These conditionals are something different to the sentence above.
No 1
If I go to Paris, I will see the Eiffel Tower [if + present, the next is future]
No 2
If I went to Paris, I would see the Eiffel Tower [if + past, the next + conditional]
No 3
If I had gone to Paris, I would have seen … [if + pluperfect, the next + conditional perfect]
Variants (very literary)
No 2
If I were to go to Paris, I would see …
Were I to go to Paris, I would see …
NB
In this construction only, the past form were to conjugates thus:
If I were to go. If we were to go.
If you were to go. If you were to go.
If he were to go. If they were to go.
No 3
Had I gone to Paris, I would have seen …