EOC WEEK REVIEW2015

ENERGIZER• What is the definition of a half life?

• Barium-122 has a half-life of 2 minutes. A fresh sample weighing 80 g was obtained. If it takes 10 minutes to set up an experiment using barium-122, how much barium-122 will be left when the experiment begins?

• Technetium-99m is used for brain scans. If a laboratory receives a shipment of 200 g of this isotope and after 24 hours only 12.5 g of this isotope remain, what is the half-life of technetium-99m?

• 6 hours

• The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g?

• 0.25 grams

Time: start 2 min 4 min 6 min 8 min 10 minMass: 80 g 40 g 20 g 10 g 5 g 2.5 g

TYPES OF BONDSIonic:

Between and metal and a nonmetal

The metal gives electrons to the nonmetal

Covalent:

Between two nonmetals

The atoms share electrons

Sometimes one atom has a greater share of the electrons, this is considered a polar bond

Metallic:

Metals bond and share their electrons

Alloys are formed

NAMING (EASY) IONIC COMPOUNDS

• What is the name of CaF2?

• Since this compound does not involve a transition metal use the name of the metal and the non-metal but change the ending to “ide.”

• Calcium fluoride

• What is the chemical formula for Potassium Sulfide?• Find the ion charges based on the periodic table, crisscross them down to determine

how many atoms of each element are needed to form the compound.

• K+1 S-2 = K2S

NAMING (HARDER) IONIC COMPOUNDS

• What is the name of Fe2O3

• Crisscross the subscripts upwards. Place the charge of the metal as a roman numeral and end the nonmetal with “ide.”

• Fe3+O2- = Iron III Oxide

• What is the chemical formula for Manganese II Sulfide• Find the ion charges based on the roman numeral for the metal and the periodic table

for the non-metal, crisscross them down to determine how many atoms of each element are needed to form the compound.

• Mn2+ S2- = Mn2S2 = MnS

NAMING COVALENT COMPOUNDS

• What is the name of N2O3 ?

• Use the subscripts as prefixes and place “ide” on the second non-metal.

• Dinitrogen trioxide

• What is the chemical formula for sulfur hexachloride?• Use the prefixes as the subscripts, no prefix means there is only one atom

of this element. The only time you do not use a prefix is when there is one atom of the first element in the name of the compound.

• SCl6

ENERGIZER

• What is the electron configuration of cobalt?• 1s22s22p63s23p64s23d7

• Which element has the electron configuration 1s22s22p63s23p64s23d104p3?• Arsenic

REMEMBER THE BLOCKS ON THE PERIODIC TABLE…

REMEMBER THE AUFBAU DIAGRAM…

ENERGIZER• Use the diagram below to answer the following questions:

• What exists in a system that is at 1 atm and 150°?

• Does H2O always exist as a solid at 0 degrees Celsius? If not, how could this be explained?

BALANCING CHEMICAL EQUATIONS

• ___ NaCl + ___ F2 → ___ NaF + ___ Cl2