Questions 1
Concentrated ammonia solution gives off ammonia gas. Concentrated hydrochloric
acid gives of hydrogen chloride gas. Ammonia, NH3, and hydrogen chloride, HCI,
are both colourless gases. Ammonia reacts with hydrogen chloride to make the
white solid ammonium chloride. Ammonia has a molar mass of 17 g/mol and
hydrogen chloride of 36.5 g/mol.
The apparatus is set up as shown.
cotton wool
soaked in concentrated
hydrochloric acid
cotton wool
soaked in concentrated
ammonia solution
А
B C D
glass tube
After ten minutes a white solid forms in the tube where the gases meet.
(a) (i) At which point, A, B, C or D, does the white solid form? Explain why the solid forms
at that point.
The solid forms at
Explanation
... [3]
(ii) Name the process by which the ammonia and hydrogen chloride gases move in the
tube.
... [1]
(iii) The experiment was repeated at a lower temperature.
Predict how the results of the experiment would be different. Explain your answer.​