25. From left to right across a period in the periodic table, elements become less ___metalic________ and more _____nonmetalic _________ in their properties.
26. Francium has 36 isotopes, but only francium-223 occurs in nature. Francium-223 spontaneously emits particles and energy, so francium-223 is a(an) ______radioctiveistoop_______ of francium.
27. At sea level, water boils at 100°C.
28. Cooking requires continuous addition of energy to the chemical reactions that are taking place. The chemical reactions involved in cooking can be described as ______endothgermic____________.
29. The _______kinetic energy_________ theory of matter states that all particles of matter are in constant motion.
30. In Rutherford’s experiments, some of the _alpha particles____aimed at gold atoms bounced back, suggesting that a solid mass was at the center of the atom.
31. You are given the melting points of three unknown substances and are asked to predict which one is an ionic compound. You would select the compound with the ________highest________ melting point.