Chemical Forums

Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: polarman on April 19, 2006, 09:37:18 AM

Title: why did i gently heat the solid with a lid? (decomposition of hydrated compound)
Post by: polarman on April 19, 2006, 09:37:18 AM

hi,
The aim of the experiment was to find x in Na2CO3.xH2O. I remmeber doing this experiment in chemistry and now its come to the write up i've forgotten exactly why i gently heated the solid with the lid on before i strongly heated it with the lid off.I remember i cooled it with the lid on so that water vapour from the air doesn't crystalise back into the solid. And i strongly heated it to drive the water from the solid.but why did i gently heati it at the start with the lid on??!?Im pretty sure its got something to do with Na2CO3.xH2O high affinity for water but why is it important to do so?

thanks xx