I would like to use "hspace" attribute instead of blank.gif

I'm using blank.gif image in my website to give a space between the elements, But in need to increase performance and reduce network calls, I'm trying to replace blank.gif image with some alternate way, and i have read in some websites like we can use "hspace" attribute in "img" element instead of using "blank.gif". I want to know what is the value i need to give for "hspace" attribute which exactly equals to "blank.gif" image.

blank.gif(1x1) ==> hspace="?"

What is the value I need to provide in the place of question mark.

Thanks in advance.