Html lang attribute is not coming on page source

I am working on a portal site to make it accessible. It is in two languages- English and French. Its developed in Razor engine MVC. My problem is while i am viewing the page source code through right click, its lang attribute is not showing but if viewing it using f12 its lang attribute is coming properly.

I have set the code for this as

<input type="hidden" id="page-culture-value" value="@this.Culture" /> 

And its javascript is given as-

var language = $("#page-culture-value").val();
$("html").attr("lang", language);