* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Reading the Periodic Table - Science
Survey
Document related concepts
Transcript
Reading the Periodic Table A way of organizing & classifying elements according to their PROPERTIES • Arranged in rows and columns Columns • The vertical (up and down) columns of the periodic table (there are 18) are called groups or families. • Elements in the same group or family have similar characteristics or properties. Rows • The horizontal rows of the periodic table are called periods. • Elements in a period are not alike in properties. • The first element in a period is usually an active solid, and the last element in a period is always an inactive gas. Rows • Atomic size (number of protons) decreases from left to right across a period. • Atomic mass (number of protons) increases from left to right across a period. Rows • Electrons are added one at a time moving from left to right across a period • The electrons of the outermost shell have increasingly strong nuclear attraction, so the electrons become closer to the nucleus • Ionization energy increases • Electronegativity increases Quick Review of electron shells Valence electrons are the outermost electrons in an atom. Rows • Metals are on the left • Non-metals are on the right