It includes twelve sovereign states (Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela), a part of France (French Guiana), and a non-sovereign area (the Falkland Islands, a British Overseas Territory though this is disputed by Argentina).
13.
There are 13 independent countries in South America.
Uruguay is located in the continent South America
Europe if you don't count Russia as part of Europe.
North America, or the Americas if you count the whole continent from the Arctic down to the Antarctic.
If you just count Central America, directly to the South you have Nicaragua and Costa Rica and to the South East you have Panama.
There are 14 countries that share a land border with the United States: Canada and Mexico are the only two countries that border the U.S. directly, while the other 12 countries are located in Central and South America.
Antarctica has the fewest inhabitants, with no permanent residents. Oceania, which includes small and sparsely populated islands, also has a lower population compared to other continents.
Africa is the continent with more than 54 countries, making it the continent with the highest number of sovereign states.
15 to be presice unless you count newzealand.
No, other continents have countries which have states. For example, Nigeria on the continent of Africa. Nigeria has 36 states and one federal capital territory. The term 'states' also refers to countries, with definable borders and international recognition. The continent of Africa has either 47 or 53 (depending on inclusion of the island nations in the count) countries or states.
Mauritius is a small piece of land surrounded by the Indian Ocean. As it is so small it could not be considered to be a continent. It is just a small island.
The count in South America that speaks Spanish is Uruguay. It is also the second smallest country in South America.
I presume you mean 'continents'. Like the number of oceans or seas, it depends on how you define a continent. I initially learned that there were 5 continents, but that lumps North and South America together as one continent; many people would count them separately, and would also count Antarctica, so that makes at least 7.