whatisasubscriptinachemicalformula?what'stherelationshipbetweenelementandstom?
我科学作业做不出~~~Science!
还有几个问题:
Howtotellasubstanceisacompoundornotacompound?
Howdoesthedensitymakethingssinkoffloatinaliquid?
chemicalformula:carbondioxideozonebackingsoda
答对一定加分!