Question

The chemical elements can be broadly divided into metals, metalloids and

nonmetals according to their shared physical and chemical properties. All metals have a

shiny appearance (at least when freshly polished); are good conductors of heat and

electricity; form alloys with other metals and form basic oxide.

Typical nonmetals have a dull, coloured or colourless appearance; are brittle when solid; are

poor conductors of heat and electricity; and have acidic oxides

(i)Basic oxides of metals turn litmus:

(a)Red to blue (b) blue to red( c) no change (d) none of these

(ii)Which non metal is essential for our life and all living beings inhale it while breathing :

(a)Oxygen (b) chlorine (c) nitrogen (d) none of these​

Answer 1

Metalloids are metallic-looking brittle solids that are either semiconductors or exist in semiconducting forms, and have amphoteric or weakly acidic oxides. Typical nonmetals have a dull, coloured or colourless appearance; are brittle when solid; are poor conductors of heat and electricity; and have acidic oxides