Aluminium
Answers are for parents and teachers.
1
Write the equation of Al burning in O₂ and find how many grams of Al₂O₃ form from 108 g of Al. (A(Al) = 27, M(Al₂O₃) = 102)
4Al + 3O₂ → 2Al₂O₃; 204 g
2
How many moles of H₂ are released when 108 g of Al dissolves in excess NaOH solution? (A(Al) = 27)
6
3
Why is it unwise to store alkaline or acidic food in aluminium cookware for long?
Alkali and acid dissolve the protective oxide film and the metal slowly dissolves.
4
Write the aluminothermy equation between Al and Cr₂O₃.
2Al + Cr₂O₃ → Al₂O₃ + 2Cr
5
Why does producing aluminium need a lot of electricity and where is it convenient to build the plants?
To reduce Al³⁺ and keep the oxide molten; near cheap electricity (hydropower) or raw material.