SharePoint 2013 REST Call to a List Item

function addListItem

// Adding a list item with the metadata provided
function addListItem(url, listname, metadata, success, failure) {
 
    // Prepping our update
    var item = $.extend({
        "__metadata": { "type": getListType(listname)}
    }, metadata);
 
    // Executing our add
    $.ajax({
        url: url + "/_api/web/lists/getbytitle('" + listname + "')/items",
        type: "POST",
        contentType: "application/json;odata=verbose",
        data: JSON.stringify(item),
        headers: {
            "Accept": "application/json;odata=verbose",
            "X-RequestDigest": $("#__REQUESTDIGEST").val()
        },
        success: function (data) {
            success(data); // Returns the newly created list item information
        },
        error: function (data) {
            failure(data);
        }
    });
 
}

function CreateTeamsite()

function CreateTeamsite() {

    var url = _spPageContextInfo.siteAbsoluteUrl;
    teamsiteValues = {
        
        "Title": $('input[id=ctl00_PlaceHolderMain_txt_name]').val(),
        "BusinessUnit": $("#sel_bu option:selected").text(),
        "Description_x002f_Purpose":"test", // $('input[id=ctl00_PlaceHolderMain_txt_purpose]').val(),
        "Members": peoplePicker_Members.GetAllUserKeys(),
        "SecondaryOwner": peoplePicker_secondaryOwner.GetAllUserKeys(),
        "Viewers":  peoplePicker_Viewers.GetAllUserKeys(),
        "Function": $("#sel_function option:selected").text(),
        "SeoKeywords": "test", //$('input[id=ctl00_PlaceHolderMain_txt_keywords]').val(),
        "Language1": $('input[id=ctl00_PlaceHolderMain_txt_language]').val(), //need to add this to the form
        "PrimaryOwner": peoplePicker_secondaryOwner.GetAllUserKeys(), //TODO: get the logged in user's login id
        "TimeZone1": $("#sel_timezone option:selected").val(),
        "TypeofTeamsite": $("input[name=type]:checked").val(),
        "URL": $('input[id=ctl00_PlaceHolderMain_txt_Url]').val()

    };

    var outputstring = "Confirm and Submit<br />";

    for (var key in teamsiteValues) {
        if (teamsiteValues.hasOwnProperty(key)) {
            outputstring += key + " -> " + teamsiteValues[key] + '<br />';
        }
    }

    $('#confirm').html(outputstring);

    submitTeamsite();

}

function submitTeamsite()
{
    var url = _spPageContextInfo.siteAbsoluteUrl;
    //var url = "http://teams.cce.com"; //TODO: pull this value from configuration later
    $.ajax({
        url: url + "/_api/web/lists/getbytitle('" + listName + "')/items",
        type: "POST",
        contentType: "application/json;odata=verbose",
        data: JSON.stringify(teamsiteValues),
        headers: {
            "Accept": "application/json;odata=verbose",
            "X-RequestDigest": $("#__REQUESTDIGEST").val()
        },
        success: function () { $('#message').text("Teamsite successfully submitted."); },
        error: function (jqXHR, textStatus, errorThrown) { $('#message').text("Update failed." + jqXHR.responseText + " " + errorThrown.toString()) }
    });

}
Update: I have found the answer to most of my question