(a) Name one laboratory apparatus/set-up for:
(i) determining the heat of neutralization:
(ii) decomposing water into hydrogen and oxygen.
(b) Outline a suitable procedure for distinguishing between glucose and cellulose using
(i) one physical test apart from tasting.
(ii) one chemical test.
(c) Draw a labelled sketch to illustrate the separation of a mixture by sublimation.
(ii) Give two examples of substances that are sublime.
(d)(i) Mention one salt which produces brown fumes on being heated strongly
(ii) What is the action of the brown fumes mentioned in (i) above on litmus.
(iii) Give one reason why it is not advisable to collect nitrogen by displacement of air [N – 14].
Explanation
(a)(i) Bomb calorimeter
(ii) Hoffman voltameter.
(b)(i) Solubility in water, glucose is soluble in water while cellulose is not soluble in water
(ii) Glucose is a strong reducing agent, it reduces Fehling's solution to red precipitate of copper (I) oxide on boiling. Cellulose does not reduce Fehling's solution
(c)(i)
(c)(ii) NH\(_4\)Cl, and iodine
(d)(i) Pb(NO\(_3\))\(_2\)
(ii) The brown fumes (NO\(_2\)) turns damp blue litmus paper red.
(iii) It is not advisable to collect nitrogen by displacement of air because it has about the same density as air.