Give the preparation method of the following compound:
`CaC_2`

Give the preparation method of the following compound: CaCO_3

Give the preparation method of the following compound: NaHCO_3

Give the preparation method of the following compound: Na_2CO_3

Select the best method for the preparation of the following compounds :

De-ionized water is prepared by the following method :

Give one method of preparation and two uses of each of the following: (i) Slaked lime (ii) Limestone (iii) Plaster of Paris.