Rationalize why chalk (calcium carbonate) has a higher melting point than motor oil (large compound made from carbon and hydrogen), which has a higher melting point than water and engages in relatively strong hydrogen bonding interactions.

How they are related to types of compounds?
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Chalk is composed of the ionic compound calcium carbonate (CaCO3). The electrostatic forces in ionic compounds are much stronger than the intermolecular forces in covalent compounds. Therefore, CaCO3 should have a much higher boiling point than the covalent compounds found in motor oil and in H2O. Motor oil is composed of nonpolar C−C and C−H bonds. The intermolecular forces in motor oil are therefore London dispersion forces. We generally consider these forces to be weak. However, with compounds that have large molar masses, these London dispersion forces add up significantly and can overtake the relatively strong hydrogen-bonding interactions in water.
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A hydrogen bond will be the electromagnetic attractive interaction between polar molecules, where hydrogen will a highly electronegative atom, for instance nitrogen, oxygen or fluorine
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