Learn Spanish (Latin America): Lo bueno es la ubicación del departamento. - The good thing is the location of the apartment.

Here, lo is a neuter article. When you combine lo with a masculine singular adjective like bueno, it turns the adjective into an abstract noun meaning "the [adjective] thing" or "that which is [adjective]". So, lo bueno translates to "the good thing". If you used el bueno, you would be saying "the good one", referring back to a specific masculine noun.

How do we know ubicación is feminine?

In Spanish, words that end in -ción (like la ubicación, la canción, or la información) are almost always feminine. That's why it takes the feminine article la.

Why is it del departamento instead of de el departamento?

Whenever the preposition de (of/from) is directly followed by the masculine article el (the), they must combine into the single word del. This is a mandatory contraction in Spanish, so you will never write de el unless the El is part of a proper name (like a city or book title).

Is departamento the normal word for apartment?