How many of the Titanic's watertight compartments broke?

The iceberg which she collided with punched a 300 foot gash in her starboard side, opening up 6 of her 16 watertight compartments to the sea.

Had the compartments extended fully all the way from the bottom to the top of the vessel, or been self-contained metal boxes, she could probably have remained afloat for long enough for other vessels to come to her aid and take off everybody on board- possibly even long enough to enable her to be towed to safety at the nearest American port. However, the compartments extended only up as far as 'E' deck- this meant that as one compartment filled, the inrush of sea water overspilled into the next one, the weight of the water pulling the bow of the vessel downwards and accelerating the flooding process in a 'domino' effect.