Antifreeze is typical a bright neon yellowish greenish color, in some cases it can be blue or red dependning on the brand name. To check if your antifreeze is what is leaking open the hood and check the liquid level in the radiator and resevoir to see if its low. Also make sure your car is not over heating.
Antifreeze is typically a bright green color. It has the viscosity of water, though don't use your bare fingers to check. Unlike oil, which is dark and generally opaque, antifreeze is translucent. If you think its antifreeze, check your coolant level in the radiator.