If it is used a title in place of a name, then yes. That would be difficult with this word, however, so usually it would be a reference to a position or status. That will not be capitalized. For example, if you say "John is our treasurer" it would not be capitalized. However, if you manged to use it as a name, like "come here, Treasurer," then it should be capitalized.
No, the word "treasurer" is not typically capitalized unless it is in a title or at the beginning of a sentence.
The word "not" is typically not capitalized in a title unless it is the first word, a proper noun, or part of a hyphenated word.
No, the word "weekend" is not supposed to be capitalized unless it is used at the beginning of a sentence or as part of a proper noun, such as the name of an event or a title.
Yes, the word "Americans" should be capitalized as it is a proper noun referring to the people of the United States of America.
Yes, "Pterodactyl" is supposed to be capitalized as it is a proper noun referring to a specific genus of pterosaur.
"British" is typically capitalized when referring to people or things from Britain or the United Kingdom.
No, it shouldn't be capitalized.
No it shouldn't be capitalized.
no
No, but the names of individual languages are capitalized.
no
It should only be capitalized if it forms part of a title.
Yes... indeed it is!
No, it is a common noun.
No it is a common noun.
Yes, the word "Americans" should be capitalized as it is a proper noun referring to the people of the United States of America.
No, but it is just one word: saltpeter.
No, except if the word is used at the beginning of a sentence.