Name three of the major ocean basins on earth

Apart of the periodic table is shown. a portion of the sixteenth and seventeenth columns of the periodic table is shown. column 16 reads eight oxygen, 16 sulfur, and 34 selenium. column 17 reads nine flourine, 17 chlorine, and 35 bromine. which of the following elements is less reactive than the others? bromine (br) oxygen (o) selenium (se) sulfur (s)

Why was the sample heated in step 5? describe the chemical principles involved in the reasoning behind this step?

What is the compliment dna strand to the following sequence: ttgactaggcta