a) Write a balanced equation for the reaction of aluminium selenide with water to Hydrogen selenide and solid aluminium hydroxide (including physical states) showing the sequence of partially balanced equations needed, including a brief description of the strategy used.
b) The density of hydrogen selenide at STP is 3.61 g litre-1. Draw a diagram of how to prepare a jar of dry hydrogen selenide, using a selection of the following equipment and materials. Include a brief description of how the arrangement achieves the desired result.
Round bottomed flask Concentrated hydrochloric acid
Additon funnel Concentrated nitric acid
Wash bottle Water
Porcelain boat Solids
Side Arm connector Calcium chloride granules
Bent glass tube Sodium chloride
Gas jar Aluminium selenide
U tube Sodium hydroxide
Straight glass tube
c) Write a balanced chemical equation for the reaction between hydrogen selenide and tin > solid tin selenide and hydrogen gas. Explain briefly why the equation accounts for the fact that the gas volume is unchanged.
d) The oxide formed when selenium burns in air, dissolves in water to give a solution of selenious acid H2SeO3. The solution conducts electricity, and turns blue litmus paper red. Give the evidence that supports classifying H2SeO3 as an acid and identify the positively charged ion present in an aqueous solution of the acid.
e) Write a balanced equation for the breakdown of selenious acid in water, and deduce the charge on the other ion that is formed.
Aluminum selenide : Al2Se3 MP:960 oC --> solid in Room Temperature
Hydrogen selenide : H2Se MP: -66 oC ; BP : -41 oC --> gas in Room Temperature
Aluminum hydroxide : Al(OH)3
Al2Se3(s) + 6 H2O(l) --> 3 H2Se(g) + 2 Al(OH)3(s)
First place coefficient 2 to Aluminum hydroxide due to two Al in the aluminum selenide..and put coefficient 3 to hydrogen selenide due to 3 Selenium in the aluminum selenide..and balance hydrogen and oxygen by putting coefficient 6 to water.
In order to get a dry hydrogen selenide, we should remove ...
Solution contains chemical equations, explanations for each question and a diagram of the experiment needed to prepare a jar of dry hydrogen selenide. 625 words.