What determines the atomic mass of an element?

A.
the sum of the protons and electrons

B.
the sum of the neutrons and the electrons

C.
the sum of the protons and the neutrons

D.
the sum of the ions and isotopes

Question

What determines the atomic mass of an element?	
 
 A.
the sum of the protons and electrons
 
 B.
the sum of the neutrons and the electrons
 
 C.
the sum of the protons and the neutrons
 
 D.
the sum of the ions and isotopes

tkhunny · Answer

What is the atomic mass of hydrogen and helium?

isuckatschool43 · Answer

5.009?

tkhunny · Answer

A - Electrons have no mass, generally speaking.
B - Electrons have no mass, generally speaking.
C - Maybe
D - What does that even mean?

Looks like the decent choices are few.

isuckatschool43 · Answer

so the only reasonable choice is c?

tkhunny · Answer

It is now time for you to quit sucking at school.  You have it.

isuckatschool43 · Answer

haha okay

isuckatschool43 · Answer

thanks.

michele_laino · Answer

hint:
here are some data:
proton mass = 938 MeV
neutron mass = 940 MeV
electron mass = 0.51 MeV
namely the mass of an electron is about $1/1840$ times the mass of a proton or of a neutron

michele_laino · Answer

so you are right!

isuckatschool43 · Answer

cool. thx

michele_laino · Answer

:)

tkhunny · Answer

Keep in mind that the Mass isn't .0000000000 because of the presence of isotopes, but that is NOT the "sum of isotopes".  That still makes no sense.