With Internet Group Management Protocol (IGMP) snooping, Layer 2 devices also can make intelligent multicast forwarding decisions by examining the contents of each frameâs Layer 3 IP header. Consider the example of a heterogeneous Layer 2 and Layer 3 network that does not use IGMP snooping.ith Internet Group Management Protocol (IGMP) snooping, Layer 2 devices also can make intelligent multicast forwarding decisions by examining the contents of each frameâs Layer 3 IP header. Consider the example of a heterogeneous Layer 2 and Layer 3 network that does not use IGMP snooping.
â¢ Volatile substances have a tendency to vaporize whereas nonvolatile substances do not have a tendency to vaporize. â¢ Volatile substances have a high vapor pressure at normal room temperature and pressure. Nonvolatile substances do not have a high vapor pressure in these conditions.
General Chemistry Dictionary. (metal,metalloid) A nonmetal is a substance that conducts heat and electricity poorly, is brittle or waxy or gaseous, and cannot be hammered into sheets or drawn into wire. Nonmetals gain electrons easily to form anions . About 20% of the known chemical elements are nonmetals.