Mapping the hex address representation to a specified conductor of system bus
The question depends on how "old school" you are.

In the days of simple 8-bit CPUs with small 16-bit address busses the addresses were directly mapped 1:1 onto the address bus.

So, for example, with say a Z80 CPU, the address 0x8000 would have signal A15 HIGH and A0-A14 all LOW.  You would then use address decoding logic (a combination of various logic gates) to make your peripheral or RAM chip react to that address.  It is most common to have one chip reacting to a range of addresses, so say you take the upper 8 bits of the address as the "chip" address, which is decoded to activate the Chip Select or Chip Enable, etc pin of the chip, and the lower 8-bits of the address are fed directly into the chip to select one of 256 (for example) internal registers or memory locations.

Things are a whole lot more complex now though.

With more powerful CPUs there is the whole concept of the "Virtual" memory map.  This is a method whereby different blocks of the memory, as seen by an application, are mapped to specific physical memory addresses.  This is usually done by a device in the CPU itself called an MMU, or Memory Management Unit.

Depending on the complexity of your CPU this could be a fairly static setup with just a few different mappings (such as in a microcontroller), or it could be a system completely controlled by the software itself, like in your PC.

In the PC, for instance, it is down to the kernel (the heart of the operating system) to map blocks of memory (real RAM, or virtual memory stored on disk) into the virtual address space.

It all gets very complicated then.