For the last 160 years, ___________has been decreasing.  Since 1832 it has possibly dropped by 5%.   a. the magnetic field strength   b. the frequency of earthquakes   c. the number of hot spots   d. the speed of P-waves On average___________ occur once every 500,000 yrs.  Wide spread evidence suggests that the last one of these events happened _____________ years ago.  (note: answer is ________ & __________)   a. magnetic reversals, 700,000   b. calderas,  90,000   c. tsunamis, 100,000   d. mantle plumes, 300,000 While discussing earth’s interior, one scientist explains, that the greater the mass of either object or the closer two objects are to each other, the stronger the ______________between them becomes.   a. gravitational attraction   b. chemical bonding strength   c. conductivity   d. repulsive force Other ways to investigate the earth’s interior involve studying, temperature, pressure, and _________   a. magnetism   b. biota   c. fractures   d. fossils

Definition Definition Connection between particles in a compound. Chemical bonds are the forces that hold the particles of a compound together. The stability of a chemical compound greatly depends on the nature and strength of the chemical bonding present in it. As the strength of the chemical bonding increases the stability of the compound also increases.