CHM 1045 -Test 1 Review questions and answers 100% verified

Acetate - C2H3O2- Ammonium - NH4+ Carbonate - CO32- Define a cation - An atom that loses an electron becomes a positively charged ion Define a covalent bond - A chemical bond formed by the sharing of a pair of electrons between atoms. Define a covalent compound - Composed of two or more nonmetal atoms bonded by sharing valence electrons. Define a group on the periodic table - The elements in any one column of the periodic table Define a metal, give its properties, and location on the periodic table - A substance that has a characteristic luster, or shine, and is generally a good conductor of heat and electricity. Except for mercury, the metallic elements are solid at room temperature. They are more or less malleable and ductile. Their location is on the left hand side of the periodic table. Define a nonmetal, give its properties, and location on the periodic table - An element that does not exhibit the characteristics of a metal. Most are gases, for example chlorine and oxygen, or solids such as phosphorus and sulfur. The solid nonmetals are usually hard, brittle substances. Bromine is the only liquid nonmetal. Their location is on the right side of the periodic table. Define a period on the periodic table - The elements in any one horizontal row of the periodic tableDefine accuracy - The closeness of a single measurement to its true value Define an anion - An atom that picks up an extra electron becomes a negatively charged atom Define an ionic bond - A chemical bond formed by the electrostatic attraction between positive and negative ions. Define atomic masses - The average atomic mass for the naturally occurring element, expressed an atomic mass units. Define atomic numbers - Z- The number of protons in the nucleus of an atom Define Law of Multiple Proportions - When two elements form more than one compound, the masses of one element in these compounds for a fixed mass of the other element are in ratios of small whole numbers. Define mass numbers - A - the total number of protons and neutrons in a nucleus Define nuclear symbols - The top number is the mass number - total protons and neutrons. The bottom number is the atomic number - number of protons. Define precision - The closeness of the set of values obtained from similar measurements of an identical quantity Define the gas phase - Easily compressible fluid, No fixed volume or shape. Define the Law of Conservation of Mass - The total mass remains constant during a chemical change (reaction) Define the Law of Definite Proportions - A pure compound, whatever its source, always contains definite or constant proportions of the elements by mass.