Answer:
Magnesium Oxide (MgO) has a higher melting point than Sodium Chloride (NaCl) which is around 2,800 degrees Celcius. This is because its Mg2+ and O2- ions have a greater number of charges, and so form stronger ionic bonds, than the Na+ and Cl– ions in Sodium Chloride.
Answer : Option D) the electrons in some metals pair up to create a magnetic field.
Explanation : Most of the metals are magnetic in nature including some exceptions. When the unpaired electrons get aligned with the magnetic field they posses magnetism. Also there are some paired electrons in metals which align themselves according to the magnetic field and create magnetism in them.
"Caesium" is the strongest reducing agent in Periodic table.
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