Rayon is different from truly synthetic fibres because :
(a) it has a silk-like appearance.
(b) it is obtained from wood pulp.
(c) its fibres can be woven like those of natural fibres.
(d) it can be dyed in wide variety of colours.
Why are metals malleable , ductile , sonorus , lustrous and why are group 1 metals are soft ?
Please explain in detail .