Final answer:
Calcium chloride (CaCl2) is classified as an inorganic compound because it does not contain carbon-hydrogen bonds. Silane (SiH4), though it involves silicon bonded to hydrogen, is also an inorganic compound since it lacks carbon in its structure.
Step-by-step explanation:
When classifying substances as organic or inorganic, a general rule of thumb is that organic compounds contain carbon atoms bonded to hydrogen atoms and typically have a carbon-based chain or ring in their structure. Inorganic compounds do not adhere to this rule and are composed of other elements.
For CaCl2, which stands for calcium chloride, we can observe that it is comprised of calcium and chlorine atoms with no carbon-hydrogen bonds present. Consequently, calcium chloride is an inorganic compound.
On the other hand, SiH4, known as silane, involves silicon bonded to hydrogen atoms. Although silicon can sometimes behave similarly to carbon and form chains and networks, compounds with silicon are not considered organic unless the silicon is directly bonded to carbon. Silane lacks carbon entirely, thus it is categorized as an inorganic compound.