The flask is heated until the boiling point of the lowest boiling substance in the mixture is reached.
(The flask; is; heated; T:until the boiling point of the lowest boiling substance in the mixture is reached) (the boiling point of the lowest boiling substance in the mixture; is reached; )
The flask the boiling point of the lowest boiling substance in the mixture
is is reached
heated T:until the boiling point of the lowest boiling substance in the mixture is reached