Avogadro defined one mole of carbon-12 atoms to have a mass of exactly 12.0 grams. Calculate the number of hydrogen atoms in 1 mole.
A) 1.38 x 1025 atoms
B) 1.66 x 1024 atoms
C) 3.98 x 1023 atoms
D) 6.02 x 1023 atoms

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.