Please help with both thank you will markbr />

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

How manyatoms of mercury are in 1.4214e+1 ml sample

Answer asap need it by wednesday morning calculate the ph of 0.02m hcl best answer will be brainliest