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Question
An atom can contain protons which have a positive charge (+) and electrons which have a negative charge (−). When an electron and a proton pair up, they become neutral (0) and cancel the charge at. Now determine the net charge:
9 protons and 12 electrons →
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Solution
9 protons and 12 electrons → (+9) + (−12)
= 9 − 12
= −3
⇒ 3 electrons ⊖⊖⊖
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