CHEMISTRY · Single correct · A Level · Chemistry · Group 7 elements (halogens) · Group 7 elements (halogens)
Problem
The correct statement is:
(1) Thermal stability of alkaline-earth-metal chlorides decreases with increasing molecular mass, but the reverse order is true for their melting points.
(2) Thermal stability of boron halides increases with decreasing molecular mass, but the reverse order is true for their melting points.
(3) Thermal stability of beryllium halides increases with decreasing molecular mass, and the same order is also true for their melting points.
(4) Thermal stability of hydrogen halides increases with decreasing molecular mass, but the reverse order is true for their melting points.