Yes -if it can, and it wants to, it will. A dog does not have the ability to think of other animals  in terms of “pet”. It regards a cat the same way as it does any other animal. Whatever the cause, if the dog wants to kill the cat and it is strong enough you may not be able to stop it. It is very easy for a dog to kill a cat - they get it by the neck, one shake, and the spine is broken. That is the reality. If it can’t do it that way it will simply maul it to death. If you really want to you can get lots of info on the internet. Then go see a psychiatrist. It is your job as dog owner to teach your dog that, in the first place, your cats are part of the household and not to be chased, let alone killed. That is one of the reasons you must get your dog from an accredited, accountable breeder because your chances are better of getting a pup that can be socialized and trained. Secondly, you should teach it not to chase other cats either, but admittedly, that is more difficult. It will save you a lot of heartache, prevent your dog from getting a bad reputation, and ultimately safeguard you against civil lawsuits if you can succeed in training your dog to leave small animals alone.