91Ó°ÊÓ

In the extraction of iron slag is produced which is: (a) \(\mathrm{CaSiO}_{3}\) (b) \(\mathrm{FeSiO}_{3}\) (c) \(\mathrm{CO}\) (d) \(\mathrm{MgSiO}_{3}\)

Which of the following gives blood red colour with KCNS? (a) \(\mathrm{Al}^{3+}\) (b) \(\mathrm{Zn}^{2+}\) (c) \(\mathrm{Fe}^{3+}\) (d) \(\mathrm{Cu}^{2+}\)

The iron obtained from blast furnace is: (a) Soft iron (b) Pig iron (c) Steel (d) Wrought iron

The nature of an aqueous solution of \(\mathrm{FeCl}_{2}\) is: (a) Basic (b) Acidic (c) Amphoteric (d) Neutral

An extremely hot copper wire reacts with steam to give: (a) \(\mathrm{Cu}_{2} \mathrm{O}\) (b) \(\mathrm{CuO}_{2}\) (c) \(\mathrm{Cu}_{2} \mathrm{O}_{2}\) (d) \(\mathrm{CuO}\)

Copper forms nitrogen oxide with dilute nitric acid but with concentrated nitric acid it gives: (a) Nitrogen dioxide (b) Nitrogen oxide (c) Nitrogen peroxide (d) Nitrogen trioxide

Cuprous ore among the following is: (a) Cuprite (b) Malachite (c) Chalcopyrites (d) Azurite

When metallic copper comes in contact with moisture, a green powdery/pasty coating can be seen over it. This is chemically known as: (a) Copper carbonate-copper sulphate (b) Copper sulphate-copper sulphide (c) Copper carbonate-copper hydroxide (d) Copper sulphide-copper carbonate

Cuprous ion is colourless, while cupric ion is coloured, because: (a) Cuprous ion has incomplete d orbital and cupric ion has a complete d orbital (b) Cuprous ion has a complete d orbital and cupric ion has incomplete \(\mathrm{d}\) orbital (c) Cuprous ion has half filled d orbital (d) Cupric ion has unpaired electrons in d orbital

Lunar caustic is: (a) \(\mathrm{NaOH}\) (b) \(\mathrm{NaNO}_{3}\) (c) \(\mathrm{AgNO}_{3}\) (d) \(\mathrm{Ag}_{2} \mathrm{SO}_{4}\)