1. (a) Label the safety hazard symbol of 4 pictograms.
(b) List down three apparatus and one safety equipment required to separate a
mixture of sand, salt and water.
2. Give the short answers for the following questions.
a) Explain the difference between the terms transparent and opaque.
b) Explain the difference between the terms dissolving and melting.
c) Distinguish between the terms of solvent and solution.
d) Explain the solution (or) solubility.
3. Forensic scientists use paper chromatography to compare links from five
different bank notes with the ink used to make genuine bank notes
Their results are shown in a chromatography in Fig below.
(i)
(ii)
(iii)
In typical paper chromatography, the start line is usually drawn in pencil. Explain
why this is so.
From fig, state which one of the bank notes is genuine.
Suggest a reason why water would not be a suitable solvent to be sued for this
chromatography.