How long does it take to write five pages of an essay or review paper on any given topic from scratch (not including referencing)?

This is really dependent on two things: 1) the degree to which the writer has some talent, or facility, with writing; and 2) how much experience the writer has with medium-length prose writing like that. Once, as a demonstration, I had a prose-writing class in the Corporate Communications program give me a random topic, and I knocked off a five-paragraph essay in 15 minutes. But that was only possible because I’ve been a quick writer sInce public school, and I’ve both taught and practised essay-writing for a while. As a rule of thumb, if you have some knowledge of the topic, and experience writing academic prose, I’d guess two hours for a five-page essay is close.