I know that copper is below hydrogen in the reactivity series, but when I looked it up, some sources said that copper reacts with acids, while some said that it doesn't. What's correct?
Copper WILL reacts with acids, but only if they are strong oxidising agents. It never gives the normal salt + hydrogen. so copper doesn't react with dilute sulfuric acid, but it does react with hot concentrated sulfuric acid Cu + 2H2SO4 --> CuSO4 + SO2 + 2H2O similarly copper will react with nitric acid because it is a potent oxidising agent.
