Calculate the molecular mass or formula mass (in amu) of each of the following substances:

Which of the following pairs of elements belong to the same groupa. h and he b. li and bec. c and pb d. ga and ge

Stoichiometry- i need with 14 and 15! an explanation would be appreciated!

Select the correct answer. why are scientific models important in the study of science? a. they always involve critical mathematical calculations. b. they scientists understand complex ideas and objects that aren’t easy to handle. c. they enable scientists to popularize their work in society. d. they are required when conducting any peer review process. e. they are necessary for turning a hypothesis into a law.