Q. 4. What is God?
A. God is a Spirit, infinite, eternal, and unchangeable, in his being, wisdom, power, holiness, justice, goodness, and truth.
(Taken from : http://www.reformed.org/documents/WSC.html )
And here are the footnotes:
(Taken from : http://www.reformed.org/documents/WSC_fn.html#fn7 )
Here is the larger catechism if you are interested: http://www.reformed.org/documents/index.html?mainframe=http://www.reformed.org/documents/larger1.html