The Big Bang probably occurred.
~30,000 B.C. North America Asian hunter-gatherers had crossed over the frozen Bering Strait to become first humans in North America.
~10,000 B.C. South America Those who crossed over on Bering Strait into North America had traveled as far south as Argentina by this point.
~6,000 B.C. Europe End of land bridge between Britain and continental Europe. Britain becomes an island.
~4,500 B.C. Brittany (France) The megalithic structures of Carnac were built.
~3,500 B.C. Wales Pentre Ifan is built.
~3,200 B.C. Ireland The Newgrange tomb is built.
Answer:
Element
magnesium, hydrogen, chlorine, sulfur
Compound
water, iron oxide
Mixture
air, salty water , dias cola.
Explanation:
Element is made up of only one type of atom and are relresented by symbols.
Compound are formed by chemical mixing of atoms of elements and have a chemical formula
Mixture are formed by simple mixing up of substances and mixture don't have chemical formula.
Assuming ammonia is the product of this reaction:
N2+3H2--->2NH3
2 mole N2 * (3 mol H2)/(1 mol N2)= 6 mol H2
You would need 6 mol of hydrogen gas to completely react with 2 mol of nitrogen.
A physical change is when something don't permanently change
