Chemistry · BGCSE / Formulae, equations and moles
StructuredPast exam questionForm 5 · BGCSE
The compound borazine was first made over 90 years ago. It was thought to have the structure shown (a six-membered ring of alternating B and N atoms, each bonded to one H).
- aWhat is the molecular formula and the empirical formula of borazine? [2]
- bIf the structural formula is correct, what will be the number of bonding electrons around one nitrogen atom in the molecule of borazine? [1]
- cLiquid borazine reacts with water to form ammonia, hydrogen and an aqueous solution of boric acid, H₃BO₃. Construct a balanced equation for this reaction, including state symbols. [2]
You'll mark your own answer against the marking guide when you hand it in.
Source: BEC BGCSE Chemistry 2008, Paper 3, Question 2(a)
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