chapter 20 lecture 1

Question 1

chlorides

Answer 1

group 1

Question 2

carbonates

Answer 2

group 2

Question 3

phosphates

Answer 3

group 3

Question 4

oxides

Answer 4

left side of transition metals and aluminum

Question 5

sulfides

Answer 5

right hand side of transition metals

Question 6

native metals

Answer 6

some of the bottom of periodic table

Question 7

what are the methods for production of metals from their ores?

Answer 7

-electrolysis
-reaction with another metal (usually a more reactive metal)
-reaction with H2 (producing water)
-reaction with C/CO (producing CO2)

Question 8

Na from NaCL

Answer 8

-Na+ e- –> Na(l) - reduction (cathode)
- 2Cl - —-> Cl2(g) + 2e- —- oxidation (anode)

sodium is very reactive so this takes place in an oxygen free environment

Question 9

production of K from KCl

Answer 9

-elemental sodium mixed with molten KCl
- K is more reactive than sodium
- equilibrium would lie towards the reactants
- K forms a gas, boils away, and is removed forcing reaction to the right

Question 10

dow process for magnesium

Answer 10

set up plant near ocean
-bring sea water into take
-make that liquid basic
-react magnesium with OH to make Mg(OH)2
-CaCO3 (sea shell or limestone)
-CaCO3 —-> CaO + C)2
-

Question 11

aluminum from bauxite ore

Answer 11

-ore contains Al2O3 and Fe2O3 as an impurity which must be removed
-ore is crushed and dissolved in water
-solution made basic forming Fe(OH)3 (s) and Al(OH)4 (aq), the aluminum is staying in solution as complex ion while iron ppts out
-iron ppt is filtered out
-CO2 bubbled through solution lowering hydroxide concentration and allows aluminum to ppt
-Al(OH)3 is heated which reforms pure Al2O3

Question 12

when aluminum is purified, what do we do with it?

Answer 12

electrolysis

Question 13

Hall/Heroult process

Answer 13

cryolite - which melts at 1000ºC

carbon at anode & cathode

aluminum reduced at cathode

anode producing carbon dioxide

Question 14

what is produced from a blast furnace?

Answer 14

iron

Question 15

what is iron ore mostly?

Answer 15

Fe2O3

Question 16

reagents in blast furnace

Answer 16

ore Fe2O3 and SiO2 (sand)
coke - C
limestone - CaCO3
air/O2

Question 17

what are the reactions that take place in blast furnace

Answer 17

2Cn(s) + O2(g) –> 2CO(s)
Fe2O3(s) + 3CO(g) __> 2Fe(l) + 3CO2(g)
CaCO3(s) –> CaO(s) + CO2(g)
CaO(s) + SiO2(s) –> CaSiO3(l)

Question 18

slag formula

Answer 18

CaSiO3 (l)

Question 19

what is slag used for

Answer 19

concrete, road beds

Question 20

pig iron

Answer 20

full of impurities such as carbon
-purified by mixing with scrap iron and more limestone and reacted at high temps in pure oxygen
-carbon is tuned to carbon dioxide and other impurites in slag
-different types of steel can be produced by introducing other metals into the iron
-200 metric tons of steel can be produced in a single blow

Question 21

how are metal sulfides heated

Answer 21

in the presence of air/oxygen

Question 22

more reactive metals form what

Answer 22

metal oxide product

Question 23

less reactive metals such as what

Answer 23

copper and mercury form pure metal

Question 24

current gold mining methods

Answer 24

chemically with cyanide and oxygen - oxygen is oxidizing agent and cyanide forms complex ion, react this with zinc and we get solid gold