[Jfalken]

Hi.
I am kind of new to orgo and this question is so stupid I just don't want to ask it in class 
Sometimes chemists lets the solution (where the reaction takes place, in the rbf for ex) cool down to room temperature and THEN add ice.
Does it mean that purified water (H2O) is added into the flask in the form of ice or does this mean that the flask itself is lowered into an ice bath?

I've seen both, hence the question.

[OrganicDan96]

some procedures call for the reaction mixture to be poured onto ice, the procedure would clearly say this and it only happens at the end of the reaction as part of the work up. when it says something like the reaction was cooled to 0°C then it means the flask was placed in an ice bath and NOT  ice to be added to the reactio.

[Jfalken]

some procedures call for the reaction mixture to be poured onto ice, the procedure would clearly say this and it only happens at the end of the reaction as part of the work up. when it says something like the reaction was cooled to 0°C then it means the flask was placed in an ice bath and NOT  ice to be added to the reactio.

So what if it says "cooled to room temperature and ice (X grams) was added"?
Does this still means place in an ice bath? If so, why would the amount of ice be of interest?
Thanks for your reply!

[OrganicDan96]

no it means ice is added to the reaction, to be honest the exact mass won't be critical just don't add too much

[jeffmoonchop]

cooling slowly to room temp will get you less, larger and nicer crystals of your product, then further cooling with ice maximises yield so the growth continues by further increasing supersaturation.

[OrganicDan96]

cooling slowly to room temp will get you less, larger and nicer crystals of your product, then further cooling with ice maximises yield so the growth continues by further increasing supersaturation.

I agree although i don't think they are doing a recrystallisation. i think this is for a quench