Three substances, X, Y

CHEMISTRY · Single correct · A Level · Chemistry · Bonding · Bonding

Problem

Three substances, X, Y, and Z have the physical properties shown. Identify X, Y, and Z.

Substance	X	Y	Z
Melting point / $^\circ\text{C}$	747	1610	2614
Boiling point / $^\circ\text{C}$	1390	2230	2850
Electrical conductivity in liquid state	High	Poor	High

(1) X: CaO, Y: NaBr, Z:

\text{SiO}_2

(2) X: CaO, Y:

\text{SiO}_2

, Z: NaBr (3) X: NaBr, Y: CaO, Z:

\text{SiO}_2

(4) X: NaBr, Y:

\text{SiO}_2

, Z: CaO