Question

You are provided with two containers made up of copper and aluminium. You are also provided with solutions of dilute HCl, dilute HNO₃, ZnCl₂ and H₂O. In which of the above containers these solutions can be kept?

Answer 1

i. In copper container:
a. Dilute HCl: Copper does not react with dilute HCl. Hence, dilute HCl can be stored in copper container.
b. Dilute HNO₃: Copper reacts with dilute HNO₃ and form copper nitrate and nitrogen monoxide gas.

Hence, dilute HNO₃ can not be stored in copper container.
c. ZnCl2 solution: As copper is less reactive than Zn, copper does not displace zinc from ZnCl2 solution. 

Therefore, ZnCl₂ solution can be stored in copper container.
d. H₂O: No reaction takes place between
copper and water. Hence, water can be stored incopper container. Dilute HCl, ZnCl₂ solution and H₂O can be stored in copper container.

ii. In aluminium container: a. Dilute HCl: Aluminium reacts with dilute HCl and forms aluminium chloride and hydrogen gas.

Due to this dilute HCl cannot be stored in aluminium container.
b. Dilute HNO₃: Aluminium reacts with dilute HNO₃ and forms aluminium oxide. Once aluminium oxide layer is formed, it does not react further. Hence, dilute HNO₃ can be stored in aluminium container.

ZnCl₂ solution : ZnCl₂ solution reacts with Al and forms aluminium chloride and zinc metal.

Hence, ZnCl₂ solution cannot be stored in aluminum container.
d. H₂O: No reaction takes place between aluminum and water (cold as well as hot water). Hence, water can be stored in aluminum container. Dilute HNO₃ and H₂O can be stored in aluminum container.