In this chapter we are listing only HTML5 attributes dedicated to non-HTML5 elements (HTML 4.01).

Check references for other HTML5 attributes:

a - f

async executes asynchronously external scripts <script>
charset specifies character encoding for entire HTML document <meta />
crossorigin it allows images from third-party locations to access the canvas (or be accessed by); or for links, it decides how the link element handles cross-origin accesses <img /><link>
disabled disables the entire fieldset group of elements <fieldset>
download for both elements, it decides if the target will download upon a click on the element or not <a><area />
form specifies which form (s) the element is referring to <object>

g - n

hreflang defines the language of the targeted area <area />
manifest for offline browsing, it describes the document's cache manifest <html>
maxlength allows the maximum number of character for the text area <textarea>
media specifies the media type of the targeted URL document <a><area />
name gives the name to a fieldset <fieldset>

o - z

rel  explains the relationship between the current document, and the one referring to <area />
reversed reverses the execution order of ordered list items <ol>
sandbox introduces (or removes) restrictions to an iframe <iframe>
scoped restricts the styles only to a parent element's tree (vertical hierarchy) <style>
sizes if rel="icon", it defines the possible size of the linked URL <link>
srcdoc defines the content of the iframe's linked document <iframe>
type specifies the media type for targeted URL <area />
wrap explains which wrapping technique to use <textarea>