The four natural isotopes of iron have atomic masses of 53.9, 55.9, 56.9, and 57.9. If these were the only isotopes of iron and they occurred in equal abundance, which would be closest to the atomic mass of iron? A. 54
B. 55
C. 56
D. 57

Bohr's model could only explain the spectra of which type of atoms? single atoms with one electron single atoms with more than one electron bonded atoms with one electron bonded atoms with more than one electron

Which of the following elements would you expect to have the lowest ionization energy value? fluorine, lithium, neon, nitrogen

The twister and runaway train are two coasters at the same amusement park. both coasters start at the same height. the coaster for the twister is twice the mass of the coaster for the runaway train. which roller coaster has greater gravitational potential energy at the start of the ride?