what the type of solid materials are typically hard, have high melting pionts and poor electrical conductivities

Ionic solids

Explanation: Ionic solids—Made up of positive and negative ions and held together by electrostatic attractions. They're characterized by very high melting points and brittleness and are poor conductors in the solid state. An example of an ionic solid is table salt, NaCl.

neutrons are in the middle of the atom and the electrons, which are much smaller.

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