Which of the following is categorized as homogeneous /pure/ element?

When hydrochloric acid dissolves in water, it is described as ____.

In the reaction CaCN2 + 3 H2O → CaCO3 + 2 NH3 [80.10]   [18.02]   [100.09]   [17.03] how many grams of NH3 will be produced when 25.0 g of CaCN2 react with excess water?

Name the molecule N2O4.

Which of the following free elements are diatomic molecules in nature?hydrogen, nitrogen, oxygen, fluorine, phosphorus, sulfur

1. Read questions very carefully. There are 50 questions and some extra credit questions.2. For the multiple-choice questions, there is only one correct answer.3. Make sure that you keep track of your time, as you will not be given additional time to complete the exam.4. Once you start the exam, you will be required to stay seated in front of the computer for the duration of your exam. Leaving your computer during the exam is considered academic dishonesty.5. If you are not sure of an answer, you should make your best-educated guess and choose an answer (don’t leave questions unanswered if you don’t know the answer – you might just get it correct if you answer your best-guess).6. As mentioned before, there are no notes, books, phones, people, or any other outside materials allowed for this exam.7. You will have 180 minutes to complete the exam!8. Good luck and RELAX!!! 

Classify the following element: calcium

He believed that people were naturally evil and that there should be a social contract between the ruler and his subjects.

Which estate in the French Revolution consisted of rich nobles who supported the King?

There are two stable isotopes, 35Cl (75.77%, 34.96885269 u) and 37Cl (24.23%, 36.96590258 u). Calculate the average atomic mass of chlorine.