A student adds excess zinc carbonate powder to a beaker containing dilute nitric acid to prepare zinc nitrate.

State two observations that would show that the nitric acid has completely reacted.
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.