How many moles is 2.17x10^23 representative particles of bromine

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins

Why does earth rotate? because earth is formed from cold gases collapsing due to gravity because the matter in the nebula that formed earth was spinning because earth forms more than 99% of the mass of the solar system because the hydrogen atoms inside the nebula fused to form helium

What are the two largest greenhouse gases