What is the atomic number for the silver?

47

is the number of protons or electrons in an atom, for example, the Atomic number of hydrogen is 1 so this means that hydrogen has 1 proton and 1 electron

there is no rule to determine the atomic number of an element , you can just memorise the important and for the rest of the elements, you can look for any of them in as I did to answer your question

Here is a quick breakdown on what the numbers on the periodic number means