Transcript 12 Notes
C H 12 T HE P ERIODIC TABLE D ISCOVERING A PATTERN Dmitri Mendeleev discovered a __________ to the elements in _____. First he wrote the ________________________ of the elements on cards. Then he arranged his cards in order of increasing _______. A pattern appeared! __________- happening at regular intervals, like days of the week. E LEMENTS WITH SIMILAR PROPERTIES OCCURRED IN A REPEATING PATTERN . D ISCOVERING A PATTERN Mendeleev predicted that elements yet to be found would _______________in his table. He was right! Missing element ____ into his gap. C HANGING THE A RRANGEMENT Some elements did not fit in the table by increasing atomic mass – so Mendeleev _________________. 1914 Henry Moseley determined the number of _________in an element. When the periodic table was arranged by increasing _______________, all elements fit the table. ____________-Repeating chemical and physical properties of elements change periodically with the elements’ atomic numbers. T HE P ERIODIC TABLE AND C LASSES OF E LEMENTS Metals – found to the _____ of the zigzag line Few __________ in the outer energy level All ________ at room temp. except Mercury (Hg) _________ _________ _________ ______ conductors METALS T HE P ERIODIC TABLE AND C LASSES OF E LEMENTS Nonmetals - found to the _____ of the zigzag line almost a complete outer energy level (Group 18 is complete) more than half are _______ at room temp. not ____________ not __________ not _______ not good conductors (good ________________) T HE P ERIODIC TABLE AND C LASSES OF E LEMENTS Metalloids – found _____ the zigzag outer energy level is ____ full have some properties of _______ have some properties of ___________ sometimes called ______________________ D ECODING THE P ERIODIC TABLE Each square on the periodic table includes: ______________ ______________ ______________ _____________ D ECODING THE P ERIODIC TABLE Period- Each ____________ row of elements Group- Each _______________of elements. Elements in the same group have ___________ properties. 5.2 G ROUPING THE E LEMENTS Group 1 – _______________ Elements in group 1 of the periodic table One __________________(electron in the highest occupied energy level) ___________because they can easily give away the 1 electron Often stored in _____ because they react violently with water and oxygen _____, ______ color, shiny and low density G ROUP 1 - A LKALI M ETALS G ROUP 2 – A LKALINE E ARTH M ETALS Group 2 – ________________________ Elements in group 2 of the periodic table ____ valence electrons ______ less reactive than alkali metals because it’s harder to give away 2 electrons _____ color, higher density G ROUP 2 – A LKALINE E ARTH M ETALS Chlorophyll contains Mg; oyster shell, pearl, and cast contain calcium G ROUP 3-12 – T RANSITION M ETALS Group 3-12 – _______________ Do not give away __________ as easily as group 1 or 2 _________valence electrons _____, ____________, higher densities and melting points (except Hg) Some transition metals from periods _______appear below the table to save space. Elements in each row tend to have similar properties Lanthanides- Actinides- ___________ , or __________. Elements listed after plutonium do not occur naturally. G ROUP 13 B ORON G ROUP Group 13 ____________ ___ metals, ___ metalloid ___ valence electrons ______ at room temp. ____ is most abundant metal in Earth’s crust reactive G ROUP 13 B ORON G ROUP G ROUP 14 C ARBON G ROUP Group 14 - ___________________ ___ valence electrons _________ at room temp. _______ is needed in body for carbs, fats, and protein. G ROUP 14 C ARBON G ROUP G ROUP 15 N ITROGEN G ROUP Group 15 __________________ ___ electrons in outer energy level most are solids at room temp. except ___ __ is 80% of the air we breathe, fertilizer G ROUP 15 N ITROGEN G ROUP G ROUP 16 O XYGEN G ROUP Group 16 _________________ ___ valence electrons ______________ __ is 20% air and needed for substances to _____ G ROUP 16 O XYGEN G ROUP G ROUP 17 H ALOGENS Group 17 _____________ __ valence electrons very ___________ _______________ poor conductors G ROUP 17 H ALOGENS G ROUP 18 N OBLE G ASES Group 18 _____________ All _____________ ___ valence electrons ________________ ___________, __________ gases at room temp. G ROUP 18 N OBLE G ASES H YDROGEN Hydrogen ____ valence electron _______,colorless, __________, __________ reactions w/ oxygen