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Give the atom notation for the following: 1) an atom with 82 p + and 126 n o 2) an atom of iron with 28 n o 3) an atom of element 29 having 34 n o

Information from the Periodic Table

Atomic Masses Measured in the unit amu –Stands for –Defined as 35 Cl = amu 50 V = amu 79 Br = amu

All Isotopes are NOT Created Equal Weighted averages

All Isotopes are NOT Created Equal Weighted averages An equation (oh crap) 35 Cl = amu –Abundance = 75.77% 37 Cl = amu –Abundance = 24.23%

35 Cl = amu –Abundance = 75.77% 37 Cl = amu –Abundance = 24.23% All Isotopes are NOT Created Equal

78.90% of all magnesium is 24 Mg  amu 10.00% of all magnesium is 25 Mg  amu of all magnesium is 26 Mg  amu A Problem! What is the average atomic mass of magnesium?

Some Algebra and a New Equation

DO NOT use If asked for If asked for ANYTHING else: Isotopes Calculation Summary

A Problem! Thallium has 2 isotopes, and. has a mass of amu and has a mass of amu. What are the percent abundances of each of the isotopes?

A Problem! Bromine has 2 isotopes, and. has a mass of amu and has a mass of amu. What are the percent abundances of each of the isotopes?

What is the percent composition of each element in strontium phosphite? Sr 3 (PO 3 ) 2 Percent Composition

A certain compound is 30.06% oxygen by mass and the rest is iron. How many kilograms of the compound are needed in order to obtain 35 kg of iron?

PeriodicTableof theElements Periodic: Having or marked by repeating patterns Table: An arrangement of words, numbers, or symbols, or combinations of them, as in parallel columns, to exhibit a set of facts or relations in a definite, compact, and comprehensive form Elements: A substance that cannot be broken down into simpler substances by chemical means

Metals: 87 of the 118 elements are metals. They appear _________________of the Periodic Table.  Some common properties of metals are:   (except ___________ which is a liquid)   

Metals

Nonmetals: Appear ___________________ of the Periodic Table. 17 elements are nonmetals. – Eleven are gases at room temperature (H, N, O, F, Ne, etc.) – Five are solids (C, P, S, Se, I) – One is a liquid (Br). – Nonmetals are poor conductors of heat and electricity.

Non-Metals

 Metalloids: Seven elements are metalloids.  Their properties are between those of metals and nonmetals.  Metalloids are semiconductors and are important to the electronics industry.

Metalloids

The Modern Periodic Table Mendeleev –Set it up the periodic table _______________________ Moseley –Set it up by ______________rather than ____________ Periodic Law –

The Modern Periodic Table Periods (series) – Groups (families) – – 2 different labeling systems

A few definitions… Main Group Elements: –Groups ____________________ Transition Elements: –Groups _____________________

Groups of Elements Vertical columns are called groups Group 1 = _____________________ Group 2 = _____________________ Group 17 = _____________________ Group 18 = _____________________

The Modern Periodic Table Main group elements –Also known as representative elements Transition metals Inner transition metals –Lanthanide series –Actinide series

Diatomic Elements Elements that exist as diatomic molecules when UNCOMBINED (meaning not in a compound with other elements).