Which of the following oxides shows electrical properties like metals?

1.  SiO2

2.  MgO

3.  SO2 (s)

4.  CrO2

 

CrO2, TiO and ReO3 are some typical metal oxides which show electrical conductivity similar to metal, While SiO2, MgO and SO2 are oxides of metal, semimetal and non-metal which do not show electrical properties.