Question

Choose the following metals to answer the questions below

(Aluminum, Copper, Calcium, Iron, Magnesium, Potassium, Nickel, Zinc)

Name a metal which

1. is manufactured by electrolysis of its molten oxide
2. is used to galvanaize Iron
3. is alloyed with Zinc to make Brass
4. reacts with aqueous copper(II)sulfate to give a pink solid
5. does not reacts with cold ${\mathrm{H}}_2\mathrm{O}$

Answer 1

Metals

Metals are opaque, lustrous elements that are good conductors of heat and electricity which is found in the left hand side of periodic table.

• Metal manufactured by electrolysis of molten oxide is Aluminum

Electrolytic reduction of Alumina(Hall-Heroult process)

Electrolytes: Alumina, Cryolite, Fluorspar (1:3:1)

At anode: $2{{\mathrm{O}}_2}^{2-}+4{\mathrm{e}}^{-}\to {\mathrm{O}}_2$

At cathode:${\mathrm{Al}}^{3+}+3{\mathrm{e}}^{-}\to \mathrm{Al}$

• Metal used to galvanize the iron$\left(\mathrm{Fe}\right)$ is Zinc

Galvanization is the process of coating of Zinc$\left(\mathrm{Zn}\right)$ on Iron$\left(\mathrm{Fe}\right)$ or Steel to prevent rusting by forming a layer of Zinc oxide$\left(\mathrm{ZnO}\right)$

• Metal alloyed with Zinc to make Brass is Copper

Alloy is the combination of metals. Brass is an alloy of Zinc and Copper

• Metal reacts with aqueous copper(II)sulfate$\left({\mathrm{CuSO}}_4\right)$ to give pink solid is Iron$\left(\mathrm{Fe}\right)$

${\mathrm{Fe}}_{\left(\mathrm{s}\right)}+{{\mathrm{CuSO}}_4}_{\left(\mathrm{aq}\right)}\to {\mathrm{FeSO}}_{4\left(\mathrm{aq}\right)}+{\mathrm{Cu}}_{\left(\mathrm{s}\right)}$

• Metal does react with cold water is Magnesium$\left(\mathrm{Mg}\right)$

As the reactivity of metals decreases in the order Potassium $\left(\mathrm{K}\right)$> Sodium $\left(\mathrm{Na}\right)$ > Calcium $\left(\mathrm{Ca}\right)$> Magnesium $\left(\mathrm{Mg}\right)$. So, tendency to react with cold water decreases.

Hence Magensium $\left(\mathrm{Mg}\right)$do not react with water.