cho 3g hỗn hợp A gồm mg, fe, al tác dụng hết với dung dịch cl dư (tn1) thu được 1.68 l khí .mặt khác cho 2g hỗn hợp A tác dụng với clo dư (tn2) thu được 5.763g hỗn hợp muối tính %mfe trong A

What are scientists who study fossils called? ( a ) astronomers. ( b ) biologists. ( c ) geologists. ( d ) paleontologists.

Astudent is trying to create a table that compares hypotheses, theories, and laws. hypothesis theory law do scientific researchers formulate it? yes yes yes does it explain why things happen? yes yes no yes yes yes is it used to make predictions? no yes yes which of the following questions would most likely fill the blank in the table? is it an intelligent guess? is it newly formulated? is it based on observations? has it been proved?

Which statement describes the phase change that occurs when dry ice is placed in an open container at room temperature?