Q4(a)(ii). Surface area of silica gel from the nitrogen monolayer
The volume of nitrogen gas at 1 atmosphere and 273 K required to cover one gram of silica gel is 0.129 dm³. Calculate the surface area of the gel if each nitrogen molecule occupies an area of 16.2×10⁻¹⁰ m². (Given NA=6.023×10²³)
Answer in brief
Surface area =562 m² per gram of gel (taking the area of one N₂ molecule as 16.2×10⁻²⁰ m²).
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All parts of Question 4
- 4(a)(i) Stark–Einstein law; why the quantum yield is often low10 marks
- 4(a)(ii) Surface area of silica gel from the nitrogen monolayer10 marks
- 4(b) Standard and actual potential of the Cu / Fe³⁺, Fe²⁺ cell10 marks
- 4(c) Schrödinger wave equation in three dimensions; meaning of ψ and ψ²10 marks