Practice question · Multiple choice
An alkaline environment activates the developing agent, yet an acid stop bath is introduced immediately afterwards. Why does this sudden shift in pH bring chemical development to a halt?
Hints
- What specific component in the developer formula relies on a high pH to function?
- How does the mechanism of stopping development differ from the mechanism of clearing the film?
Show the answer
C. It quickly neutralises the accelerator that energises the agent
Why
Development requires an alkaline pH maintained by the accelerator to reduce silver halides; dropping the pH neutralises this activation without stripping unexposed halides, which remains the fixer's task.
Practise Developing the Negative
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