Mos commonly 2 elements combine.
examples: H2, O2
b
Explanation:
February 7, 1863, was the day John Newlands published a paper outlining what would be known as “The Law of Octaves”. Newlands discovered if he ordered the known elements by increasing atomic weight, the chemical properties of the elements would be similar for every eighth group
Answer:
Both are pure substances and a compound
Alfred Wegner was the first person to propose the idea that all seven continents were all one supercontinent called "Pangea". Everyone considered his theory to be a joke until he found evidence to back up his theory. His evidence was the matching mountain ranges, fossils, certain species, and more over different continents. Also that all the seven continents fit together like puzzle pieces. I hope this helps! :)