Experiment reports
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Using passive voice to focus on what is done | page 4 of 4 |
The use of passive voice in Preparing and identifying ammonia
The following text from a chemistry textbook talks about the preparation and
identification of ammonia. The words in bold are verbs in passive voice 
:
Preparing and identifying ammonia
Objectives
To prepare a small amount of ammonia in the laboratory
To carry out identification tests on it
Materials and apparatus
ammonium chloride
calcium hydroxide
pH paper
filter paper
6 test tubes with racks
1 glass rod
mortar and pestle
1 spatula
Procedure
| 1. | About 1 spatula measure of solid ammonium chloride was mixed with about 2 spatula measures of solid calcium hydroxide with a mortar and pestle. |
| 2. | The mixture was put into a test tube. |
| 3. | The mixture was heated gently. |
| 4. | After heating, the gas evolved was fanned towards the experimenter's nose. |
| 5. | A piece of wet red litmus paper was then placed at the mouth of the test tube. |
Results
| 1. | The gas smelled of ammonia. |
| 2. | The litmus paper turned blue. |
Conclusions
Ammonia is formed when an ammonium salt is heated with an alkali.
Two tests which can be used to indicate the presence of ammonia are its characteristic smell and wet litmus paper turning blue.
An equation for the reaction is:
2NH4Cl(s) + Ca(OH)2 ® 2NH3(g) + CaCl2(s) + 2H2O(l)
(Adapted from Doyle, P. and Lo, M.L. (1994) Chemistry Today: Experimental Workbook, Teacher's Edition. Longman, pp 94-95.)
Introduction
The use of passive voice in Preparing and identifying ammonia
