Yes, Harry Potter and the Chamber of Secrets was released on Pottermore in 2012.
Chapters 5-11 of Harry Potter and the Chamber of Secrets was released on the 18th September 2012.
Harry Potter and the Chamber of Secrets wasn't released for a long time after the opening. You should now be able to access it after completing the first book.
The hairpin is collected in chapter 4 of Harry Potter and the Chamber of Secrets in the moment titled "Lucius Malfoy". It can be found in the hair of the blonde girl.
The letter was found inside the Letters from School moment. This has since been removed from Pottermore.
Chapter 5 of Harry Potter and the Chamber of Secrets was released on the 18th September 2012.
You don't interact with the diary in this chapter.
Once you have completed the first book, the second book will open for you to explore.
Chapter 5-11 were released on the 18th September 2012.
You have to click on the spells coming from the wands. They are identified by the colours.
Just the first but they are working on the Chamber of Secrets.
Chapters 5 to 11 of Harry Potter and the Chamber of Secrets were released on the 18th September 2012.