The mass number of an atom is equal to the sum of protons and neutrons in the nucleus. A helium atom has 2 protons and 2 neutrons. What is the mass number of this atom?

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

3) in peaches, [oh]=3.16x10-11 m a) find [h+ ] b) what is the ph? c) is the solution acidic, basic, or neutral?

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.