OCR trends and patterns question

Carbon tetrachloride (CCl4) does not mix or react with water, but silicon tetrachloride (SiCl4) reacts violently with water.

Why? Whhhhy?

Reply 1

Flicker

allodoxa

Carbon tetrachloride (CCl4) does not mix or react with water, but silicon tetrachloride (SiCl4) reacts violently with water.

Why? Whhhhy?

i imagine it's something to do with the bonding - silicon is simple molecular and carbon has its crazy bonding? i'm not really sure but that's not actually on the syllabus anyway, it's just an aside comment for the SAQs yeah?

Reply 2

ResidentEvil

allodoxa

Carbon tetrachloride (CCl4) does not mix or react with water, but silicon tetrachloride (SiCl4) reacts violently with water.

Why? Whhhhy?

Was this on a past paper? coz I've never seen it before. But if i was to answer, I'd say ummmm CCl4 has no groups that can hydrogen bond with water, it could only form Van der Waal forces with inorganic solvents, and for SiCl4 ummmm is slightly trickier, but I'd hazard a guess and say because it is an acidic chloride where water molecules can hydrolyse it and break it up into SiO2 and HCl releasing a white precipitate.

Hope this is alrite.

Infact now uve made me think "why" chlorides and oxides react with water as they do.......eek.

Reply 3

allodoxa

No it's not a past paper question, don't worry.

I was just wondering WHY all these things react the way they do, because it isn't really explained anywhere.

But so long as they don't ask us for explanations in the exams, I suppose it doesn't matter.