When to use capital and capitol ?

Before we discuss about "when to use capital and capitol", we have to know the definition of the meaning of the word Capital and Capitol.

Capital definition : The word capital has numerous meanings. As a noun, it denotes: (1) a city that is the seat of the government for a country or state (2) an amount of money or property. As an adjective it denotes (1) an uppercase letter (3) first rate, excellent (3) main, principal.

Capitol definition :  The Capitol is the building that serves as the seat of government for the United States Congress. It is located in Washington on top of Capitol Hill.

Example how tu use :

The Capitol is the main building of the US Congress.
(Capitol is also known as the Statehouse.)

The capital of England is London.

That was a capital speech you made from the Capitol.
(capital = first rate, excellent)

Do you have any capital invested in her business?
(...any money or property invested)

Our capital concern is that everyone gets fed during the electricity failure.
(...main or principal concern)

In German, all nouns start with a capital letter.
(Ich habe eine Katze = I have a cat.)

    The ability to expand depends on access to capital. [Capital Spectator]

    Wilderness — with a capital “W,” according to the Wilderness Act — offers the values of “solitude,” and “primitive, unconfined recreation.” [New York Times]

    The House will take up a bill this week adding one statue of a District luminary to the halls of the Capitol. [Washington Post]

    In 1972, the U.S. Supreme Court banned capital punishment, but the decision was overturned in 1976. [Columbia Missourian]

    You are a capital fellow, Planchet. [Ten Years Later, Alexandre Dumas]

    What it does have is the state capitol building, Vermont State House, with its impressive gold leaf dome backdropped by the wooded hills of Hubbard Park. [Guardian]