3.
Jessica was investigating the rusting of iron. She set up five experiments as shown below and left
the test-tubes for three
days.
ㅂ
iron nail in distilled water
iron nail in tap water
which has been boiled to
remove dissolved gases
E
iron nail in vinegar
iron nail in sea water
Jessica wrote the following results in her book.
iron nail and a chemical
to absorb water vapour
observation
Test-tube
A
nail slightly rusty
B
nail still shiny
nail still shiny
CDE
nail very rusty
nail slightly rusty, bubbles of gas seen
Explain why the nails had not rusted I. test tubes B and C
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