how can i solve it?
2007-09-07 09:22:51 · 3 answers · asked by shima 1 in Science & Mathematics ➔ Chemistry
you can't add up the mass of a proton and the mass of an electron to get the mass of a hydrogen atom.
look at the periodic table under H and see atomic mass. that is a weighted average mass for all the isotopes of Hydrogen. and it is mass / mole in grams or mass / atom in AMU's (atomic mass units). depending on how you want to answer this either
1) answer in amu/atom = 1.00794 AMU
2) 1.00794 g/mole x (1 mole/ 6.022x10^23 atoms) =
your choice
2007-09-07 09:50:18 · answer #1 · answered by Dr W 7 · 1⤊ 0⤋
1 mole of hydrogen has a mass of 1.00795 grams, right?
And 1 mole of hydrogen contains 6.022e23 atoms.
So.... the mass of a single hydrogen atom is:
(1.00795 g/mol) / (6.022e23 atoms/mol) = 1.674e-24 grams.
If you need to know for physics purposes, you'd best report your answer in kilograms: 1.674e-27 kg.
EDIT: I should point out that this is the AVERAGE mass of a hydrogen atom, since naturally occuring hydrogen has a small amount of deuterium in it.
2007-09-07 16:30:41 · answer #2 · answered by Lucas C 7 · 1⤊ 0⤋
Hydrogen = 1 proton + 1 electron
Mass of H = mass of p + mass of e
= 1.6x10^-27 kg + 9.11x10^-31 kg
= 1.600911 x 10^-27 kg
2007-09-07 16:28:23 · answer #3 · answered by nyphdinmd 7 · 1⤊ 1⤋