Understanding Vivarium Substrates. By A. C. Highfield. Libyan tortoise-this tortoise requires a sandy, dry substrate. If maintained on grass or upon a moist substrate it will suffer shell and respiratory infections.Along with heating and lighting systems, the choice of substrate in tortoise vivaria and terraria often causes a great deal of confusion to keepers.Some substrates are excellent, others positively lethal.nderstanding Vivarium Substrates. By A. C. Highfield. Libyan tortoise-this tortoise requires a sandy, dry substrate. If maintained on grass or upon a moist substrate it will suffer shell and respiratory infections.
In their general structure, heterocyclic compounds resemble cyclic organic compounds that incorporate only carbon atoms in the ringsâfor example, cyclopropane (with a three-carbon-atom ring) or benzene (with a six-carbon-atom ring)âbut the presence of the heteroatoms gives heterocyclic compounds physical and chemical properties that are often quite ...
Covalent or molecular compounds form when elements. electrons in a covalent bond to form molecules. Molecular compounds are electrically neutral. Ionic compounds are (usually) formed when a metal reacts with a nonmetal (or a polyatomic ion). Covalent compounds are formed when two nonmetals react with each other.