Why is the processes address space a continuous block in RAM? I need some clarification regarding how the process address space is organized in memory. I went through basic concepts of virtual memory and adress translation and according to the size of the page, it seems that a virtual adress can have its equivalent physical address located anywhere in RAM, it that right ?

I saw the following representation of RAM :



It seems that processes address space is continuous in RAM, how come ? I though that we could have, for example, the stack of a process(or some part of it) located at a totally different region of RAM than, for example, the heap.
The term virtual memory applies as soon as there is a mapping from logical (process specific) addresses to physical one.  The mapping may be as simple as adding a base to the logical address to get the physical one or as complex as the segmentation followed by paging of x86.  The representation you show seems to assume the first.