CE Chem

A

(1) Using scrubbers to remove sulphur dioxide from flue gas in a power station.

CaO + SO2 → CaSO3

∵CaO is a base and SO2 is an acidic gas.
∴The reaction is neutralization.

(2) Using catalytic converters to remove nitrogen oxides in car exhaust.

2CO + 2NO → 2CO2 + N2

The reaction doesn't involve a base or an acid.
It is actually a redox reaction.

(3) Using sodium hydroxide solution to remove copper(II) ions in industrial waste water.

Cu2+ + 2OH- →Cu(OH)2

The reaction doesn't involve a base or an acid.
It is actually a precipitation.

A
scrubber neutralize souphure dioxide (acidic gas)

reaction of (2) :
2NO--> N2 + O2
with catalyst of platinum

i don't know how sodium hydroxide remove copper (II), but the reaction does not involve hydrongen ion or acidic anhydride, so it is not neutralization