Nothing but pairs of a kind

The objective is to reduce a given word to nothing in a series of steps.

At each step, remove every occurrence of an adjacent pair of letters of your choosing.

For example:

• Problem: Reduce CONCOCTION to nothing in three steps
• Solution:
1. Step 1: Remove every occurrence of "TI": CONCOCTION -> CONCOCON
2. Step 2: Remove every occurrence of "CO": CONCOCON -> NN
3. Step 3: Remove every occurrence of "NN": NN -> 

Please solve the three following problems in the given number of steps:

1. Reduce ARCHITECTURE to nothing in four steps

2. Reduce HETEROJUNCTION to nothing in five steps

3. Reduce CHLOROFLUOROCARBON to nothing in six steps

ARCHITECTURE:

ARCHITECTURE -> ARCTECTURE
ARCTECTURE -> AREURE
AREURE -> AU
AU ->

HETEROJUNCTION:

HETEROJUNCTION -> HETERONCTION
HETERONCTION -> HETERCTI
HETERCTI -> HETETI
HETETI -> HI
HI ->

CHLOROFLUOROCARBON:

CHLOROFLUOROCARBON -> CHLOROFLUORORBON
CHLOROFLUORORBON -> CHLOFLUBON
CHLOFLUBON -> CHLOFLON
CHLOFLON -> CHFN
CHFN -> CN
CN ->

I know this has already been answered, but I gave it a go without cheating so I want to answer too!

ARCHITECTURE:

1 - "HI" > ARCTECTURE
2 - "CT" > AREURE
3 - "RE" > AU
4 - "AU" >

HETEROJUNCTION:

1 - "JU" > HETERONCTION
2 - "ON" > HETERCTI
3 - "RC" > HETETI
4 - "ET" > HI
5 - "HI" >

CHLOROFLUOROCARBON:

1 - "CH" > LOROFLUOROCARBON
2 - "CA" > LOROFLUORORBON
3 - "OR" > LOFLUBON
4 - "UB" > LOFLON
5 - "LO" > FN
6 - "FN" >

• Nice work! And you revealed a little secret about the making of this puzzle. I could only find a handful of words that had a single, unique solving path with the qualities that I wanted (CONCOCTION, ARCHITECTURE, ANTAGONISTIC, IMPLEMENTING, SPECTROSCOPY, and HETEROJUNCTION). The word CHLOROFLUOROCARBON actually has seven different solving paths, all slight variations of each other. You managed to find a different variation from the one that @juicifer presented! Feb 2 at 15:41