Cliffs AP Chemistry, 3rd Edition

(d) Restatement: Identify:

oxidizing agent: MnO 4 - _iaq a species that accepts electrons from another

reducing agent: Fe2+(aq) a species that furnishes electrons to another

species oxidized: Fe2+(aq) Oxidation Is Losing (electrons)

species reduced: MnO 4 - _iaq Reduction Is Gaining (electrons)

(e) Restatement: Moles of iron in the sample of ore.

This problem can be done by using the factor-label method.

.

'

'

'

.

mL KMnO

mL KMnO sol n

liter KMnO sol n

liter KMnO sol n

mole KMnO

mole KMnO

moles Fe

1

13 889

1000

1

1

0 100

1

5

4

4

4

4

4

4

2

#

##

+

= 6.94 × 10 –3mole Fe2+= 6.94 × 10 –3mole Fe

(because all of the Fe was converted to Fe2+)

(f) Restatement: Mass percent of iron in the ore.

%%.

..
whole

part

g ore

mole Fe

mole Fe

gFe

(^100) 6 893
0 00694
1
55 85
==##×100% = 5.62%
Part II: Specific Topics