Which statement describes a concept included in the wave-mechanical model of the atom? 1. Positrons are located in shells outside the nucleus. 2. Neutrons are located in shells outside the nucleus. 3. Protons are located in orbitals outside the nucleus. 4. Electrons are located in orbitals outside the nucleus?

Modern weaponry has increased the number of deaths in wars and violent conflicts.

What amount of heat is exchanged when 106.2 grams of substance y goes from a liquid at 35 degrees celsius to a solid at the same temperature? melting point of substance y = 35 degrees c; δhvaporization = 3.67 j/mol; δhfusion = 3.30 j/mol. mwsubstance y = 28.22 g/mol. −12.4 j −3.51 x 102 j 1.24 x 101 j 351 j

28. which is not a reason that water is used to store spent fuel rods from nuclear power plants? water increases the speed of the chain reaction in the fuel rods. water protects nuclear power plant workers from the high temperature and radiation of the fuel rods. water acts as a radiation shield to reduce the radiation levels. water cools the spent rods. salts action