I can't locate back splash key

Try 3 keys to the right of your p.
Will need to do shift as well.
This is if you mean "Backslash"

This depends on your keyboard. However, look near the enter key for a the one marked in a slash from Top Left to Bottom Right. That is the direction of a back slash.

soho1, I found it IS called a "Backsplash",

soho1, I found it IS called a "Backsplash",

By whom? I've always referred to it as the backslash

@all

Just to be clear:
Slash: is this key (/)
Backslash: is this key (\)
Solidus looks like (/) but is a different ASCII code
Reverse Solidus looks like (\) but is a different ASCII code
Solidus and Reverse Solidus are used in typesetting.