That the different structures of allotropes might affect the properties of solids?

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.

The excretory system, need answers for all: )

Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.