Resource Guide for Chemistry Quiz-2020.docx

Resource Guide for Chemistry Quiz Atoms are made up of three particles: protons, neutrons, and electrons; atoms are always neutral (equal numbers of protons and electrons) Chemical formulas are used to describe chemical equations; made up of element symbols and subscripts Chemical equations are use...

Resource Guide for Chemistry Quiz Atoms are made up of three particles: protons, neutrons, and electrons; atoms are always neutral (equal numbers of protons and electrons) Chemical formulas are used to describe chemical equations; made up of element symbols and subscripts Chemical equations are used to describe chemical reactions; made up of chemical formulas, coefficients, and a yield sign Chemical reactions can result in: phases change, energy change, and color change Ionic compounds are formed between positive and negative ions (forming ionic bonds), ionic compounds usually occur between a metal and a non-metal, they tend to be brittle, and exist as solids at room temperature, conduct electricity when dissolved in water Covalent compounds usually occur between two nonmetals, electrons are shared (form covalent bonds), they tend to exist as liquids at room temperature, and will dissolve Acids occur between hydrogen ions and another element; they have a pH of 0-6.9, and can be corrosive to body tissue, TASTE SOUR Bases occur between hydroxide ions and another element; they have a pH of 7.1-14, and can be corrosive to body tissue, TASTE BITTER pH of 7 is NEUTRAL Water can exist in all three forms on the Earth, its solid phase is less dense than its liquid phase; water has many unique properties (surface tension, cohesion, adhesion, high heat capacity), most important INORGANIC compound (does not contain carbon and hydrogen) The Periodic Table of Elements shows the relationships between all of the natural occurring and artificial elements; the elements are categorized in groups (or families) and periods based on repeating patterns, most (2/3rds) of the Table is made of METALS Elements in the same GROUPS have similar properties The groups are named as follows: alkali metals, alkaline-earth metals, transition metals, boron group, nitrogen group, carbon group, oxygen group, halogens, and Noble Gases There are 18 GROUPS and 7 PERIODS Groups or families go up and down (like a column) and periods go left to right Most reactive metals Groups 1 and 2’ Most reactive non-metals Group 17 Most unreactive elements Group 18