One of the most confusing things for new users who are creating their own web pages using page builders is that they cannot make additional spaces. To ease this out Empty element has been designed that helps in giving structure to those web pages.
This element has 3 main tabs: General, Design & Advanced.
In General we only have another General tab that has Space option where you can set the amount of space in pixels. Its default value is set to 50 px.
For details on Design & Advanced tabs read the articles.