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Calculation Question

This seems so simple, yet I have no idea how to get the answer for part b.



(table of masses of proton, neutron and electron)

a) Calculate the mass of an atom of hydrogen which is made from a proton and anelectron. Answer: 1.6734 × 10–24 g

b) Calculate the mass of one mole of such hydrogen atoms giving your answer to fourdecimal places. (The Avogadro constant, L = 6.0225 × 1023 mol–1)

The answer is meant to be 1.0078 g
Someone explain please!!
Proton Mass= 1.6725x10^-24 g
Electron Mass= 0.0009x10^-24 g

Add these 1.6725x10^-24 g

Mass= 1.6725x10^-24 x 6.0255x10^23
Mass= 1.007g
Im not sure why you multiply the mass (protons+electrons+neutrons if so) by the avogrados constant, does this work for every element if someone could clarify please and if theres a formula quote it please

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