How many atoms of K are present in 195.49 grams of K?

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

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have

12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer