may be this can help :
<?php
if ( have_posts() ) {
$counter = 0;
while ( have_posts() ) {
if(($counter%5) == 0 ){?>
<div class= "col-md-12"> call the loop tags of the curent post to show data that you want </div>
<?php
}
else{?>
<div class= "col-md-6"> call the loop tags of the curent post to show data that you want </div>
<?php }
$counter++;
} // end while
} // end if
?>
In case to limit post to 10 post only:
<?php
$wp = new WP_Query(array('posts_per_page'=>10));
if ( $wp->have_posts() ) {
$counter = 0;
while ( $wp->have_posts() ) {
if(($counter%5) == 0 ){?>
<div class= "col-md-12"> call the loop tags of the curent post to show data that you want </div>
<?php
}
else{?>
<div class= "col-md-6"> call the loop tags of the curent post to show data that you want </div>
<?php }
$counter++;
} // end while
} // end if
?>
you have to call all the tags like : the_title(), the_content()
preceded by $wp , but not obligation
%5(modulo operator)