Practise explaining high melting points by linking giant ionic lattices, oppositely charged ions and the energy needed to overcome attractions.
This is a question about metals and their compounds.
In the absence of air, magnesium reacts with sulfur to form the ionic compound magnesium sulfide, MgS
Explain why magnesium sulfide has a very high melting point.
M1 strong (electrostatic) force of attraction
M2 between magnesium ions /Mg2+ and sulfide ions /S2− ions
M3 large amount/lot of (heat/thermal) energy needed to overcome forces/attraction
ALLOW strong ionic bonds but No M1 or M2 if between atoms/molecules or any reference to intermolecular forces / covalent bonds
ACCEPT between oppositely charged ions
ACCEPT between positive and negative ions
ACCEPT large amount/lot of (heat/thermal) energy needed to break the bonds
IGNORE more energy
No M3 if reference to overcoming / breaking intermolecular forces / covalent bonds