Horizontally aligning a h3 and h5 - html

Question

I am trying to use bootstrap to align my h3 headings with my h5 so that they are in line with each other.
EDIT
I am trying to use the already available bootstrap and avoid changing the css unless absolutely necessary.
Here is a screen to demonstrate what i mean.
E.g. First name should line up with address 1, last name with address 2 etc.
here is the code I have.
<div class="row ">
<div class="col-md-4 ">
<h3>First Name</h3>
<h3>Last Name</h3>
<h3>Week.</h3>
<h3>Code.</h3>
</div>
<div class="col-md-4 ">
<h5>Address 1</h5>
<h5>Address 2</h5>
<h5>Address 3</h5>
<h5>Country</h5>
</div>
</div>

Answer 1

That's not what headers are for. (semantically incorrect, search engines won't like this)
I suggest to simply use a table for this (it IS tabular data) and use different CSS rules for td:first-child and td:nth-child(2) in order to get the different font sizes.
.x {
width: 100%;
}
.x td {
padding: 10px;
font-family: sans-serif;
font-weight: light;
}
.x td:first-child {
font-size: 24px;
width: 60%;
}
.x td:nth-child(2) {
font-size: 16px;
width: 40%;
}
<table class="x">
<tr>
<td>First Name</td>
<td>Address 1</td>
</tr>
<tr>
<td>Last Name</td>
<td>Address 2</td>
</tr>
<tr>
<td>Week.</td>
<td>Address 3</td>
</tr>
<tr>
<td>Code.</td>
<td>Country</td>
</tr>
</table>

Answer 2

Better not to mess with the h3/h5 heights, and use multiple rows instead. E.g. what if one of the texts becomes so long that it wraps? Then you can say bye-bye to your aligned layout. That will never happen if you use multple rows:
<div class="row">
<div class="col-md-4">
<h3>First Name</h3>
</div>
<div class="col-md-4">
<h5>Address 1</h5>
</div>
</div>
<div class="row">
<div class="col-md-4">
<h3>Last Name</h3>
</div>
<div class="col-md-4">
<h5>Address 2</h5>
</div>
</div>
<div class="row">
<div class="col-md-4">
<h3>Week.</h3>
</div>
<div class="col-md-4">
<h5>Address 3</h5>
</div>
</div>
<div class="row">
<div class="col-md-4">
<h3>Code.</h3>
</div>
<div class="col-md-4">
<h5>Country</h5>
</div>
</div>
Apart from all this: I agree with the remarks by others that you shouldn't be using h3/h5 in the first place. Headers are intended to define relations between logical units of text, so <h5> is the header of a sub-sub section of text inside a chapter of text that is headed by a <h3> tag.

Answer 3

set same line-heigt, margins, and padding for h3&h5 in css styles