State two physical properties on the basis of which metals can be distinguished from non-metals.
Two physical properties that differentiate metals from non-metals are-
(i) Metals, except mercury & gallium are solids at room temperature while non-metals, except bromine are solids or gases at room temperature.
(ii) Metals are malleable and ductile while non-metals are non-malleable & non-ductile
(iii) Metals are lustrous while non-metals, except diamond & graphite which are allotropes of carbon as well as iodine, are non-lustrous.