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Can somebody help me witg this physics a level question?

image.jpgI know it may seem simple but i cant gey the right answer for question 3a). How would you find the charge?
Original post by yacinesen
image.jpgI know it may seem simple but i cant gey the right answer for question 3a). How would you find the charge?


It has lost 2 electrons, therefore it has lost the charge of 2 electrons. What is the charge on an electron?
Reply 2
Original post by Protostar
It has lost 2 electrons, therefore it has lost the charge of 2 electrons. What is the charge on an electron?


-1.60*10^-19
Original post by yacinesen
-1.60*10^-19


Yep - so this atom, that started off with no charge, has lost 2 electrons. So it’s lost 2 lots of -1.60 x 10-19C. Can you work it out from here?
Reply 4
TD52B3D87-468A-4097-B804-14C10A0FECC9.jpg.jpeg

This is the answer i got before but its wrong. Im doing it wrong right?
Original post by yacinesen
TD52B3D87-468A-4097-B804-14C10A0FECC9.jpg.jpeg

This is the answer i got before but its wrong. Im doing it wrong right?


Think of it this way - in an atom, the number of protons = the number of electrons, and protons and electrons have equal but opposite charges. This means the resultant charge of an atom is 0, atoms are neutral.

As two electrons have been lost, this means that there are 2 more protons than electrons in the atom, so it is now an ion. Therefore the charge of this ion is the same as the charge on 2 protons (the same as the charge on 2 electrons, except positive as the atom has lost negative charge)

Does this make sense? :smile:
Reply 6
Original post by Protostar
Think of it this way - in an atom, the number of protons = the number of electrons, and protons and electrons have equal but opposite charges. This means the resultant charge of an atom is 0, atoms are neutral.

As two electrons have been lost, this means that there are 2 more protons than electrons in the atom, so it is now an ion. Therefore the charge of this ion is the same as the charge on 2 protons (the same as the charge on 2 electrons, except positive as the atom has lost negative charge)

Does this make sense? :smile:


Yeh makes perfect sense and now I understand. Thanks for your help and time!!
Original post by yacinesen
Yeh makes perfect sense and now I understand. Thanks for your help and time!!


Awesome! No problem :h:

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