Предмет: Химия, автор: AlyonaKramarenko15

какие частицы обусловливают массу атома? определите массовое число элемента номер 15 в переодической таблице.

Ответы

Автор ответа: ДядюшкаХимик

0

Массу атома обуславливают протоны и нейтроны. Практически вся масса атома сосредоточена в ядре, массой электронов можно пренебречь.
№15 имеет фосфор, его массовое число 31 (самый распространенный изотоп)

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