What do you call the positive ion?, What makes isotopes different from each other?, If you have 10 protons and 9 neutrons, what would the mass number be?,  What is an ion?, The atoms of the SAME element but with different MASSES, If an atom becomes NEGATIVELY charged, what has happened?.

排行榜

視覺風格

選項

切換範本

恢復自動保存: ?