All i5 CPUs starting from Sandy Bridge (almost 5 years old now) support DDR3L memory. It is the same memory type, only with lower voltage.
But I would not advise mixing RAMs. For example, if you buy that acer with memory being already inside, you can bet it is not the same model as yours in terms of manufacturer, clocks, timings, etc. You need a matching pair for best compatibility and stability, otherwise you might experience issues.