Which compund in the solid state has a hight melting point and conducts electricty when it is liquefied ?

Question

1) carbon dioxide
2) silicon dioxide
3) hydrogen chloride
4) potassium cholride

Please choose the answer and explain why ? to get the points

Answer 1

high melting point means the compound is a solid at room temp. this leaves out CO2 and HCl.

only ionic compounds or metals conduct electricity in molten state. this leaves out SiO2.

the answer is KCl, 4).